arm: Fixes for asm-flags vs thumb1 and ilp32

arm: Fixes for asm-flags vs thumb1 and ilp32

Thumb1 cannot support asm-flags currently, because we don't expose the
flags register to the compiler.  Disable the support for that case.

Adjust the asm-flag-6 test for aarch64 ilp32 correctness.

gcc/
	* config/arm/arm-c.c (arm_cpu_builtins): Use def_or_undef_macro
	to define __GCC_ASM_FLAG_OUTPUTS__.
	* config/arm/arm.c (thumb1_md_asm_adjust): New function.
	(arm_option_params_internal): Swap out targetm.md_asm_adjust
	depending on TARGET_THUMB1.
	* doc/extend.texi (FlagOutputOperands): Document thumb1 restriction.

gcc/testsuite/
	* testsuite/gcc.target/arm/asm-flag-3.c: Skip for thumb1.
	* testsuite/gcc.target/arm/asm-flag-5.c: Likewise.
	* testsuite/gcc.target/arm/asm-flag-6.c: Likewise.
	* testsuite/gcc.target/arm/asm-flag-4.c: New test.

	* testsuite/gcc.target/aarch64/asm-flag-6.c: Use %w for
	asm inputs to cmp instruction for ILP32.

From-SVN: r278443