* common.opt (fprofile-generate,fprofile-use): Add.
	* gcc.c (LINK_COMMAND_SPEC): Arrange -fprofile-generate to imply -lgcov
	* opts.c (profile_arc_flag_set, flag_profile_values_set,
	flag_unroll_loops_set, flag_tracer_set,
	flag_value_profile_transformations_set,
	flag_peel_loops_set): New static variables.
	(common_handle_option): Deal with -fprofile-generate/-fprofile-use
	* invoke.texi (-fprofile-generate, -fprofile-use): Describe.

From-SVN: r74976