gdb: Add --with-python-libdir to gdb's --configuration output

Commit:

  commit d13c7322fe
  Date:   Fri Jan 17 00:10:22 2020 +0000

      gdb: Allow more control over where to find python libraries

Added a new configuration option --with-python-libdir, but failed to
add this option to the output of 'gdb --configuration'.  This commit
fixes this mistake.

gdb/ChangeLog:

	* top.c (print_gdb_configuration): Print --with-python-libdir
	configuration value.

gdb/ChangeLog

@@ -1,3 +1,8 @@
+2020-06-23  Andrew Burgess  <andrew.burgess@embecosm.com>
+
+	* top.c (print_gdb_configuration): Print --with-python-libdir
+	configuration value.
+
 2020-06-22  Philippe Waroquiers  <philippe.waroquiers@skynet.be>
 
 	* NEWS: Mention change to the alias command.

gdb/top.c

@@ -1567,6 +1567,15 @@ This GDB was configured as follows:\n\
              --without-python\n\
 "));
 #endif
+#ifdef WITH_PYTHON_LIBDIR
+  fprintf_filtered (stream, _("\
+             --with-python-libdir=%s%s\n\
+"), WITH_PYTHON_LIBDIR, PYTHON_LIBDIR_RELOCATABLE ? " (relocatable)" : "");
+#else
+  fprintf_filtered (stream, _("\
+             --without-python-libdir\n\
+"));
+#endif
 
 #if HAVE_LIBDEBUGINFOD
   fprintf_filtered (stream, _("\