Inline all support functions for sin and cos

The support functions for sin and cos have a lot of identical
functionality, so inlining them gives a pretty decent jump in
functionality: ~19% in the sincos function.  On SPEC2006 this
translates to about 2.1% in the tonto test.

	* sysdeps/ieee754/dbl-64/s_sin.c (do_cos): Mark as inline.
	(do_cos_slow): Likewise.
	(do_sin): Likewise.
	(do_sin_slow): Likewise.
	(slow): Likewise.
	(slow1): Likewise.
	(slow2): Likewise.
	(sloww): Likewise.
	(sloww1): Likewise.
	(sloww2): Likewise.
	(bsloww): Likewise.
	(bsloww1): Likewise.
	(bsloww2): Likewise.
	(cslow2): Likewise.