copy-acl: enhance Solaris ACL error handling

copy-acl: enhance Solaris ACL error handling

Gracefully handle EOPNOTSUPP in qcopy_acl and qset_acl.  These
functions, as used in coreutils, were causing the test suite to fail
on Solaris 8 i386 with ZFS-backed NFSv3 mounts.  The failures included
errors such as:

FAIL: cp/backup-dir
cp: preserving permissions for `y/x': Operation not supported on
transport endpoint

* lib/copy-acl.c (qcopy_acl): Also ignore EOPNOTSUPP.
* lib/set-mode-acl.c (qset_acl): Likewise.

Signed-off-by: Ben Walton <bwalton@artsci.utoronto.ca>
Signed-off-by: Eric Blake <eblake@redhat.com>