s390/s390-64 missing xattr exports

[Jakub Jelinek]

Hi!

sysdeps/unix/sysv/linux/s390/s390-64/Versions
doesn't export xattr syscalls, although it seems those are there since
2.5.21. E.g. alpha on the other side, although it defines them in unistd.h,
doesn't actually include them in syscall table.

Wouldn't it be better to export all the symbols in s/u/s/linux/Versions, in
s/u/s/linux/Makefile add all the files for those
syscalls and write -ENOSYS wrappers for the arches which don't provide them?
Like that, we wouldn't miss when cris, sh, hppa or some other architecture
adds those syscalls...

	Jakub