Fix dg-require-* syntax

Fix dg-require-* syntax

	* gcc.dg/Wattribute-alias.c: Pass emtpy arg to dg-require-ifunc.

	* gcc.c-torture/execute/20030125-1.c: Pass emtpy arg to dg-require-weak.

	* gcc.dg/torture/ftrapv-2.c: Pass empty arg to dg-require-fork.

	* gcc.target/i386/pr84723-1.c: Remove dg-require-ifunc.
	* gcc.target/i386/pr84723-2.c: Likewise.
	* gcc.target/i386/pr84723-3.c: Likewise.
	* gcc.target/i386/pr84723-4.c: Likewise.
	* gcc.target/i386/pr84723-5.c: Likewise.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@271476 138bc75d-0d04-0410-961f-82ee72b054a4