fortran, libgfortran: -mabi=ieeelongdouble I/O

fortran, libgfortran: -mabi=ieeelongdouble I/O

The following patch adds the compiler and library side of -mabi=ieeelongdouble
I/O support.

2022-01-04  Jakub Jelinek  <jakub@redhat.com>

gcc/fortran/
	* trans-io.c (transfer_namelist_element): Use gfc_type_abi_kind,
	formatting fixes.
	(transfer_expr): Use gfc_type_abi_kind, use *REAL128* APIs even
	for abi_kind == 17.
libgfortran/
	* libgfortran.h (__acoshieee128, __acosieee128, __asinhieee128,
	__asinieee128, __atan2ieee128, __atanhieee128, __atanieee128,
	__coshieee128, __cosieee128, __erfieee128, __expieee128,
	__fabsieee128, __jnieee128, __log10ieee128, __logieee128,
	__powieee128, __sinhieee128, __sinieee128, __sqrtieee128,
	__tanhieee128, __tanieee128, __ynieee128): Formatting fixes.
	(__strtoieee128, __snprintfieee128): Declare.
	* io/io.h (default_width_for_float, default_precision_for_float):
	Handle kind == 17.
	* io/size_from_kind.c (size_from_real_kind, size_from_complex_kind):
	Likewise.
	* io/read.c (set_integer, si_max, convert_real, convert_infnan,
	read_f): Likewise.
	* io/write.c (extract_uint, size_from_kind, set_fnode_default):
	Likewise.
	* io/write_float.def (DTOA2Q, FDTOA2Q): Define for HAVE_GFC_REAL_17.
	(determine_en_precision, get_float_string): Handle kind == 17.
	* io/transfer128.c: Use also for HAVE_GFC_REAL_17, but don't drag in
	libquadmath if POWER_IEEE128.
	* Makefile.am (comma, PREPROCESS): New variables.
	(gfortran.ver): New goal.
	(version_arg, version_dep): Use gfortran.ver instead of
	$(srcdir)/gfortran.map.
	(gfortran.map-sun): Depend on and use gfortran.ver instead of
	$(srcdir)/gfortran.map.
	(BUILT_SOURCES): Add $(version_dep).
	* Makefile.in: Regenerated.
	* gfortran.map (GFORTRAN_8): Don't export
	_gfortran_transfer_complex128, _gfortran_transfer_complex128_write,
	_gfortran_transfer_real128 and _gfortran_transfer_real128_write if
	HAVE_GFC_REAL_17 is defined.
	(GFORTRAN_12): Export those here instead.