testsuite: i386: Fix gcc.target/i386/no-callee-saved-1.c etc. on Solaris/x86

The gcc.target/i386/no-callee-saved-[12].c tests FAIL on Solaris/x86:

FAIL: gcc.target/i386/no-callee-saved-1.c scan-assembler-not push
FAIL: gcc.target/i386/no-callee-saved-2.c scan-assembler-not push

In both cases, the test expect the Linux/x86 default of
-fomit-frame-pointer, while Solaris/x86 defaults to
-fno-omit-frame-pointer.

So this patch explicitly specifies -fomit-frame-pointer.

Tested on i386-pc-solaris2.11 (as and gas) and i686-pc-linux-gnu.

2024-01-30  Rainer Orth  <ro@CeBiTec.Uni-Bielefeld.DE>

	gcc/testsuite:
	* gcc.target/i386/no-callee-saved-1.c: Add -fomit-frame-pointer to
	dg-options.
	* gcc.target/i386/no-callee-saved-2.c: Likewise.