wrap math.h for M_PI et al in target/i386 tests

wrap math.h for M_PI et al in target/i386 tests

Most but not all of the tests that expect M_PI, M_PI_2 and/or M_PI_4
to be defined in math.h explicitly exclude one target system that does
not satisfy this non-standard assumption.

This patch introduces a wrapper header that includes math.h and then
conditionally supplies the missing non-standard macro definitions.
With that, we can drop the dg-skip-if "no M_PI" exclusions.

for  gcc/testsuite/ChangeLog

	* gcc.target/i386/math_m_pi.h: New.
	* gcc.target/i386/sse4_1-round.h: Use it.
	* gcc.target/i386/pr73350.c: Likewise.
	* gcc.target/i386/avx512f-vfixupimmpd-2.c: Likewise.
	* gcc.target/i386/avx512f-vfixupimmps-2.c: Likewise.
	* gcc.target/i386/avx512f-vfixupimmsd-2.c: Likewise.
	* gcc.target/i386/avx512f-vfixupimmss-2.c: Likewise.
	* gcc.target/i386/avx512f-vfixupimmss-2.c: Likewise.
	* gcc.target/i386/avx-ceil-sfix-2-vec.c: Likewise.  Drop
	dg-skip-if "no M_PI".
	* gcc.target/i386/avx-cvt-2-vec.c: Likewise.
	* gcc.target/i386/avx-floor-sfix-2-vec.c: Likewise.
	* gcc.target/i386/avx-rint-sfix-2-vec.c: Likewise.
	* gcc.target/i386/avx-round-sfix-2-vec.c: Likewise.
	* gcc.target/i386/avx512f-ceil-sfix-vec-1.c: Likewise.
	* gcc.target/i386/avx512f-ceil-vec-1.c: Likewise.
	* gcc.target/i386/avx512f-ceilf-sfix-vec-1.c: Likewise.
	* gcc.target/i386/avx512f-ceilf-vec-1.c: Likewise.
	* gcc.target/i386/avx512f-floor-sfix-vec-1.c: Likewise.
	* gcc.target/i386/avx512f-floor-vec-1.c: Likewise.
	* gcc.target/i386/avx512f-floorf-sfix-vec-1.c: Likewise.
	* gcc.target/i386/avx512f-floorf-vec-1.c: Likewise.
	* gcc.target/i386/avx512f-rint-sfix-vec-1.c: Likewise.
	* gcc.target/i386/avx512f-rintf-sfix-vec-1.c: Likewise.
	* gcc.target/i386/avx512f-round-sfix-vec-1.c: Likewise.
	* gcc.target/i386/avx512f-roundf-sfix-vec-1.c: Likewise.
	* gcc.target/i386/avx512f-trunc-vec-1.c: Likewise.
	* gcc.target/i386/avx512f-truncf-vec-1.c: Likewise.
	* gcc.target/i386/sse2-cvt-vec.c: Likewise.
	* gcc.target/i386/sse4_1-ceil-sfix-vec.c: Likewise.
	* gcc.target/i386/sse4_1-ceil-vec.c: Likewise.
	* gcc.target/i386/sse4_1-ceilf-sfix-vec.c: Likewise.
	* gcc.target/i386/sse4_1-ceilf-vec.c: Likewise.
	* gcc.target/i386/sse4_1-floor-sfix-vec.c: Likewise.
	* gcc.target/i386/sse4_1-floor-vec.c: Likewise.
	* gcc.target/i386/sse4_1-floorf-sfix-vec.c: Likewise.
	* gcc.target/i386/sse4_1-floorf-vec.c: Likewise.
	* gcc.target/i386/sse4_1-rint-sfix-vec.c: Likewise.
	* gcc.target/i386/sse4_1-rint-vec.c: Likewise.
	* gcc.target/i386/sse4_1-rintf-sfix-vec.c: Likewise.
	* gcc.target/i386/sse4_1-rintf-vec.c: Likewise.
	* gcc.target/i386/sse4_1-round-sfix-vec.c: Likewise.
	* gcc.target/i386/sse4_1-round-vec.c: Likewise.
	* gcc.target/i386/sse4_1-roundf-sfix-vec.c: Likewise.
	* gcc.target/i386/sse4_1-roundf-vec.c: Likewise.
	* gcc.target/i386/sse4_1-roundsd-4.c: Likewise.
	* gcc.target/i386/sse4_1-roundss-4.c: Likewise.
	* gcc.target/i386/sse4_1-trunc-vec.c: Likewise.
	* gcc.target/i386/sse4_1-truncf-vec.c: Likewise.

From-SVN: r274157