Improve performance of sinf and cosf

Improve performance of sinf and cosf

The second patch improves performance of sinf and cosf using the same
algorithms and polynomials.  The returned values are identical to sincosf
for the same input.  ULP definitions for AArch64 and x64 are updated.

sinf/cosf througput gains on Cortex-A72:
* |x| < 0x1p-12 : 1.2x
* |x| < M_PI_4  : 1.8x
* |x| < 2 * M_PI: 1.7x
* |x| < 120.0   : 2.3x
* |x| < Inf     : 3.0x

	* NEWS: Mention sinf, cosf, sincosf.
	* sysdeps/aarch64/libm-test-ulps: Update ULP for sinf, cosf, sincosf.
	* sysdeps/x86_64/fpu/libm-test-ulps: Update ULP for sinf and cosf.
	* sysdeps/x86_64/fpu/multiarch/s_sincosf-fma.c: Add definitions of
	constants rather than including generic sincosf.h.
	* sysdeps/x86_64/fpu/s_sincosf_data.c: Remove.
	* sysdeps/ieee754/flt-32/s_cosf.c (cosf): Rewrite.
	* sysdeps/ieee754/flt-32/s_sincosf.h (reduced_sin): Remove.
	(reduced_cos): Remove.
	(sinf_poly): New function.
	* sysdeps/ieee754/flt-32/s_sinf.c (sinf): Rewrite.