Don't mark g_option_error_quark() as const, to be consistent with all the

Don't mark g_option_error_quark() as const, to be consistent with all the

2004-11-23  Matthias Clasen  <mclasen@redhat.com>

	* glib/goption.h: Don't mark g_option_error_quark() as const,
	to be consistent with all the other error_quark functions.
	(technically they are const, but since these are called only
	in error paths, giving the compiler better optimization
	opportunities doesn't matter much)