mips.exp (setup_mips_tests): Set mips_abi to the default ABI.

mips.exp (setup_mips_tests): Set mips_abi to the default ABI.

gcc/testsuite/
	* gcc.target/mips/mips.exp (setup_mips_tests): Set mips_abi to the
	default ABI.  Split mips_forced_abi into mips_forced_abi and
	mips_forced_regs.
	(is_gp32_flag): Return true for -mabi=32.
	(is_gp64_flag): New function.  Handle 64-bit -mabi options.
	(dg-mips-options): Use is_gp64_flag instead of checking specifically
	for -mgp64.  Update after the mips_forced_abi split.  Handle -mabi=*.
	Don't force an ABI for -mgp32 or -mfp32 if the flags contain -mabi=*.
	* gcc.target/mips/pr33256.c: Remove -mips3 requirement.
	* gcc.target/mips/save-restore-1.c: Use -mabi=32 instead of -mgp32.
	* gcc.target/mips/save-restore-2.c: Likewise.
	* gcc.target/mips/save-restore-3.c: Likewise.
	* gcc.target/mips/save-restore-4.c: Likewise.

From-SVN: r128966