Modernise yyerror

Modernise yyerror

Newer versions of bison emit a prototype for yyerror
	void yyerror (const char *);
This clashes with some of our old code that declares yyerror to return
an int.  Fix that in most cases by modernizing yyerror.  bfin-parse.y
uses the return value all over the place, so for there disable
generation of the prototype as specified by posix.

binutils/
	* arparse.y (yyerror): Return void.
	* dlltool.c (yyerror): Likewise.
	* dlltool.h (yyerror): Likewise.
	* sysinfo.y (yyerror): Likewise.
	* windmc.h (yyerror): Likewise.
	* mclex.c (mc_error): Extract from ..
	(yyerror): ..here, both now returning void.
gas/
	* config/bfin-parse.y (yyerror): Define.
	(yyerror): Make static.
	* itbl-parse.y (yyerror): Return void.
ld/
	* deffilep.y (def_error): Return void.