S390: Add configure check to detect support for arch13.
Add two configure checks which detect if arch13 is supported
by the assembler at all - by explicitely setting the machine -
and if it is supported with default settings.
ChangeLog:
* config.h.in (HAVE_S390_MIN_ARCH13_ZARCH_ASM_SUPPORT,
HAVE_S390_ARCH13_ASM_SUPPORT): New undefine.
* sysdeps/s390/configure.ac: Add checks for arch13 support.
* sysdeps/s390/configure: Regenerated.