Use upper case for more metasyntactic variables in gdb

I noticed a few places where a Usage line in gdb did not use upper
case for metasyntactic variables.  This patch fixes all the instances
I found.

Tested on x86-64 Fedora 28.

gdb/ChangeLog
2019-01-04  Tom Tromey  <tom@tromey.com>

	* compile/compile.c (_initialize_compile): Use upper case for
	metasyntactic variables.
	* symmisc.c (_initialize_symmisc): Use upper case for
	metasyntactic variables.
	* psymtab.c (_initialize_psymtab): Use upper case for
	metasyntactic variables.
	* demangle.c (demangle_command): Use upper case for metasyntactic
	variables.
	(_initialize_demangler): Likewise.
	* ax-gdb.c (_initialize_ax_gdb): Use upper case for metasyntactic
	variables.

gdb/ChangeLog

@@ -1,3 +1,17 @@
+2019-01-04  Tom Tromey  <tom@tromey.com>
+
+	* compile/compile.c (_initialize_compile): Use upper case for
+	metasyntactic variables.
+	* symmisc.c (_initialize_symmisc): Use upper case for
+	metasyntactic variables.
+	* psymtab.c (_initialize_psymtab): Use upper case for
+	metasyntactic variables.
+	* demangle.c (demangle_command): Use upper case for metasyntactic
+	variables.
+	(_initialize_demangler): Likewise.
+	* ax-gdb.c (_initialize_ax_gdb): Use upper case for metasyntactic
+	variables.
+
 2019-01-03  Tom Tromey  <tom@tromey.com>
 
 	* tui/tui-source.c (tui_set_source_content): Use xstrdup.

gdb/ax-gdb.c

@@ -2751,7 +2751,7 @@ _initialize_ax_gdb (void)
   add_cmd ("agent", class_maintenance, agent_command,
 	   _("\
 Translate an expression into remote agent bytecode for tracing.\n\
-Usage: maint agent [-at location,] EXPRESSION\n\
+Usage: maint agent [-at LOCATION,] EXPRESSION\n\
 If -at is given, generate remote agent bytecode for this location.\n\
 If not, generate remote agent bytecode for current frame pc address."),
 	   &maintenancelist);
@@ -2759,7 +2759,7 @@ If not, generate remote agent bytecode for current frame pc address."),
   add_cmd ("agent-eval", class_maintenance, agent_eval_command,
 	   _("\
 Translate an expression into remote agent bytecode for evaluation.\n\
-Usage: maint agent-eval [-at location,] EXPRESSION\n\
+Usage: maint agent-eval [-at LOCATION,] EXPRESSION\n\
 If -at is given, generate remote agent bytecode for this location.\n\
 If not, generate remote agent bytecode for current frame pc address."),
 	   &maintenancelist);

gdb/compile/compile.c

@@ -941,7 +941,7 @@ indicate the end of the expression."),
 	       _("\
 Evaluate a file containing source code.\n\
 \n\
-Usage: compile file [-r|-raw] [filename]\n\
+Usage: compile file [-r|-raw] [FILENAME]\n\
 -r|-raw: Suppress automatic 'void _gdb_expr () { CODE }' wrapping."),
 	       &compile_command_list);
   set_cmd_completer (c, filename_completer);

gdb/demangle.c

@@ -188,7 +188,7 @@ demangle_command (const char *args, int from_tty)
   name = arg_start;
 
   if (*name == '\0')
-    error (_("Usage: demangle [-l language] [--] name"));
+    error (_("Usage: demangle [-l LANGUAGE] [--] NAME"));
 
   if (!lang_name.empty ())
     {
@@ -262,7 +262,7 @@ Use `set demangle-style' without arguments for a list of demangling styles."),
 
   add_cmd ("demangle", class_support, demangle_command, _("\
 Demangle a mangled name.\n\
-Usage: demangle [-l language] [--] name\n\
+Usage: demangle [-l LANGUAGE] [--] NAME\n\
 If LANGUAGE is not specified, NAME is demangled in the current language."),
 	   &cmdlist);
 }

gdb/psymtab.c

@@ -2236,8 +2236,8 @@ _initialize_psymtab (void)
 {
   add_cmd ("psymbols", class_maintenance, maintenance_print_psymbols, _("\
 Print dump of current partial symbol definitions.\n\
-Usage: mt print psymbols [-objfile objfile] [-pc address] [--] [outfile]\n\
+Usage: mt print psymbols [-objfile OBJFILE] [-pc ADDRESS] [--] [OUTFILE]\n\
-       mt print psymbols [-objfile objfile] [-source source] [--] [outfile]\n\
+       mt print psymbols [-objfile OBJFILE] [-source SOURCE] [--] [OUTFILE]\n\
 Entries in the partial symbol table are dumped to file OUTFILE,\n\
 or the terminal if OUTFILE is unspecified.\n\
 If ADDRESS is provided, dump only the file for that address.\n\

gdb/symmisc.c

@@ -1072,8 +1072,8 @@ _initialize_symmisc (void)
 
   add_cmd ("symbols", class_maintenance, maintenance_print_symbols, _("\
 Print dump of current symbol definitions.\n\
-Usage: mt print symbols [-pc address] [--] [outfile]\n\
+Usage: mt print symbols [-pc ADDRESS] [--] [OUTFILE]\n\
-       mt print symbols [-objfile objfile] [-source source] [--] [outfile]\n\
+       mt print symbols [-objfile OBJFILE] [-source SOURCE] [--] [OUTFILE]\n\
 Entries in the full symbol table are dumped to file OUTFILE,\n\
 or the terminal if OUTFILE is unspecified.\n\
 If ADDRESS is provided, dump only the file for that address.\n\
@@ -1083,7 +1083,7 @@ If OBJFILE is provided, dump only that file's minimal symbols."),
 
   add_cmd ("msymbols", class_maintenance, maintenance_print_msymbols, _("\
 Print dump of current minimal symbol definitions.\n\
-Usage: mt print msymbols [-objfile objfile] [--] [outfile]\n\
+Usage: mt print msymbols [-objfile OBJFILE] [--] [OUTFILE]\n\
 Entries in the minimal symbol table are dumped to file OUTFILE,\n\
 or the terminal if OUTFILE is unspecified.\n\
 If OBJFILE is provided, dump only that file's minimal symbols."),