* configure.in: Add configuration test for long double type existing
and set flag _HAVE_LONG_DOUBLE if true. Fix INIT_ARRAY (.init_array)
and _LDBL_EQ_DBL tests to not link so that will work with
cross-compilers.
* configure: Regenerated.
* Makefile.in: Ditto.
* newlib.hin: Add _HAVE_LONG_DOUBLE flag.
* libc/include/math.h: Change non-builtin defines for HUGE_VAL,
HUGE_VALF, and HUGE_VALL to be constant expressions. Add definitions
for the non-builtin case for INFINITY and NAN. Gate HUGE_VALL and
union __ldmath definitions with (new) _HAVE_LONG_DOUBLE.
*libm/common/s_infconst.c: Change definitions to use values from
float.h instead of non-so-portable integer forms. Mark as being
deprecated (because now removed from math.h, are not used anywhere
in Newlib, itself).
* libc/include/math.h (HUGE_VALF, HUGE_VALL): New.
* libm/common/Makefile.am: Add s_infconst.c support.
* libm/common/Makefile.in: Regenerated.
* libm/common/s_infconst.c: New file with float and
long double infinity support added.
* libm/math/Makefile.am: Remove s_infconst.c support.
* libm/math/Makefile.in: Regenerated.
* libm/math/s_infconst.c: Moved to common directory.
* libm/mathfp/Makefile.am: Remove s_infconst.c support.
* libm/mathfp/Makefile.in: Regenerated.
* libm/mathfp/s_infconst.c: Moved to common directory.