psymtab cleanup patch 2/3

psymtab cleanup patch 2/3

This patch adds two typedefs:
expand_symtabs_file_matcher_ftype
expand_symtabs_symbol_matcher_ftype

It also renames the NAME_MATCHER argument in expand_symtabs_matching.
The function is named expand_symtabs_matching and it takes a name_matcher
argument.  Name of what?  The symtab?  A symbol?
I made it SYMBOL_MATCHER to make it clearer.

	* symfile.h (expand_symtabs_file_matcher_ftype): New typedef.
	(expand_symtabs_symbol_matcher_ftype): New typedef.
	(quick_symbol_functions.expand_symtabs_matching): Update to use.
	expand_symtabs_file_matcher_ftype, expand_symtabs_symbol_matcher_ftype.
	* symfile.c (expand_partial_symbol_names): Update to use
	expand_symtabs_symbol_matcher_ftype.
	* dwarf2read.c (dw2_expand_symtabs_matching): Update to use
	expand_symtabs_file_matcher_ftype, expand_symtabs_symbol_matcher_ftype.
	Arg name_matcher renamed to symbol_matcher.
	* psymtab.c (recursively_search_psymtabs): Update to use
	expand_symtabs_symbol_matcher_ftype.  Arg name_matcher renamed to
	sym_matcher.
	(expand_symtabs_matching_via_partial): Update to use
	expand_symtabs_file_matcher_ftype, expand_symtabs_symbol_matcher_ftype.
	Arg name_matcher renamed to symbol_matcher.