PR c/68833
	* common.opt (Wmissing-noreturn): Add Warning option.
	* opts-common.c (control_warning_option): If opt is
	alias_target with alias_arg, set arg to it.

	* c.opt (Wmissing-format-attribute, Wnormalized): Add Warning option.

	* c-c++-common/pr68833-1.c: New test.
	* c-c++-common/pr68833-2.c: New test.

From-SVN: r231624