Minor testsuite tweaks

gcc/testsuite/
	* gnat.dg/valid_scalars2.adb: Remove -O0 option.
	* gnat.dg/validity_check3.ads: Rename to...
	* gnat.dg/valid_scalars3.ads: ...this.
	* gnat.dg/validity_check3.adb: Rename to...
	* gnat.dg/valid_scalars3.adb: ...this.
3 files changed