Define make_symbol in the header.

Define make_symbol in the header.

To reach good performances these functions should be inlined (yet this is
to measure precisely).  To this end they must be available to the caller.

	* data/lalr1.cc (b4_symbol_constructor_definition_): Qualify
	location_type with the class name.
	Since will now be output in the header, declare "inline".
	No longer use b4_symbol_constructor_specializations, but
	b4_symbol_constructor_definitions in the header.
	Don't call it in the *.cc file.