Don't declare float / long double Bessel functions for XSI POSIX (bug 18977).

Don't declare float / long double Bessel functions for XSI POSIX (bug 18977).

The float and long double versions of Bessel function (j0f, y1l, etc.)
are not in POSIX; only the double versions are.  This patch
accordingly limits the declarations of those functions to __USE_MISC,
and fixes the conform/ test expectations which matched the previous
incorrect declarations.

Tested for x86_64 and x86 (testsuite, and that installed stripped
shared libraries are unchanged by this patch).

	[BZ #18977]
	* math/bits/mathcalls.h
	[!__USE_MISC && __USE_XOPEN && !__MATH_DECLARING_DOUBLE] (j0): Do
	not declare.
	[!__USE_MISC && __USE_XOPEN && !__MATH_DECLARING_DOUBLE] (j1):
	Likewise.
	[!__USE_MISC && __USE_XOPEN && !__MATH_DECLARING_DOUBLE] (jn):
	Likewise.
	[!__USE_MISC && __USE_XOPEN && !__MATH_DECLARING_DOUBLE] (y0):
	Likewise.
	[!__USE_MISC && __USE_XOPEN && !__MATH_DECLARING_DOUBLE] (y1):
	Likewise.
	[!__USE_MISC && __USE_XOPEN && !__MATH_DECLARING_DOUBLE] (yn):
	Likewise.
	* conform/data/math.h-data
	[!ISO99 && !ISO11 && !POSIX && !POSIX2008] (j0f): Do not expect
	function.
	[!ISO99 && !ISO11 && !POSIX && !POSIX2008] (j1f): Likewise.
	[!ISO99 && !ISO11 && !POSIX && !POSIX2008] (jnf): Likewise.
	[!ISO99 && !ISO11 && !POSIX && !POSIX2008] (y0f): Likewise.
	[!ISO99 && !ISO11 && !POSIX && !POSIX2008] (y1f): Likewise.
	[!ISO99 && !ISO11 && !POSIX && !POSIX2008] (ynf): Likewise.
	[!ISO99 && !ISO11 && !POSIX && !POSIX2008] (j0l): Likewise.
	[!ISO99 && !ISO11 && !POSIX && !POSIX2008] (j1l): Likewise.
	[!ISO99 && !ISO11 && !POSIX && !POSIX2008] (jnl): Likewise.
	[!ISO99 && !ISO11 && !POSIX && !POSIX2008] (y0l): Likewise.
	[!ISO99 && !ISO11 && !POSIX && !POSIX2008] (y1l): Likewise.
	[!ISO99 && !ISO11 && !POSIX && !POSIX2008] (ynl): Likewise.