Simplify range location creation in C++ parser.

Simplify range location creation in C++ parser.

Many places in the parser follow the same pattern of capturing the location
of the last lexed token, either before or after lexing it, and then using
that as the end of a location range; this can be simplified by passing the
lexer to make_location and grabbing the token location there.

	* parser.c (make_location): Add overload taking cp_lexer* as last
	parameter.

From-SVN: r273516