[C] Print ", ..." rather than ", ..." in diagnostics

pp_separate_with inserts a space after the separator, so there's
no need to add whitespace before "..." as well.

2019-09-30  Richard Sandiford  <richard.sandiford@arm.com>

gcc/c-family/
	* c-pretty-print.c (pp_c_parameter_type_list): Avoid printing
	two spaces between a comma and "...".

gcc/testsuite/
	* gcc.dg/Wincompatible-pointer-types-1.c (f1): Expect only one
	space between the comma and "...".

From-SVN: r276302

gcc/c-family/ChangeLog

@@ -1,3 +1,8 @@
+2019-09-30  Richard Sandiford  <richard.sandiford@arm.com>
+
+	* c-pretty-print.c (pp_c_parameter_type_list): Avoid printing
+	two spaces between a comma and "...".
+
 2019-09-27  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c++/88203

gcc/c-family/c-pretty-print.c

@@ -525,7 +525,7 @@ pp_c_parameter_type_list (c_pretty_printer *pp, tree t)
       if (!first && !parms)
 	{
 	  pp_separate_with (pp, ',');
-	  pp_c_ws_string (pp, "...");
+	  pp_string (pp, "...");
 	}
     }
   pp_c_right_paren (pp);

gcc/testsuite/ChangeLog

@@ -1,3 +1,8 @@
+2019-09-30  Richard Sandiford  <richard.sandiford@arm.com>
+
+	* gcc.dg/Wincompatible-pointer-types-1.c (f1): Expect only one
+	space between the comma and "...".
+
 2019-09-30  Martin Jambor  <mjambor@suse.cz>
 
 	PR ipa/91853

gcc/testsuite/gcc.dg/Wincompatible-pointer-types-1.c

@@ -7,6 +7,6 @@ int
 f1 (void)
 {
   int (*x) ();
-  x = f; /* { dg-error "assignment to 'int \\(\\*\\)\\(\\)' from incompatible pointer type 'void \\(\\*\\)\\(int,  \.\.\.\\)'" } */
+  x = f; /* { dg-error "assignment to 'int \\(\\*\\)\\(\\)' from incompatible pointer type 'void \\(\\*\\)\\(int, \.\.\.\\)'" } */
   return x (1);
 }