staging: lustre: llite: drop acl from cache

Commit b8a7a3a6 change get_acl() for posix xattr to always cache
the ACL which increases the reference count. That reference count
can be reduced by have ll_get_acl() call forget_cached_acl() which
it wasn't. When an inode gets deleted by Lustre the POSIX ACL
reference count is tested to ensure its 1 and if not produces an error.
Since forget_cached_acl() was not called Lustre started to complain.
This patch changes ll_get_acl() to call forget_cached_acl().
Signed-off-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/llite/file.c

@@ -3124,6 +3124,7 @@ struct posix_acl *ll_get_acl(struct inode *inode, int type)
 	spin_lock(&lli->lli_lock);
 	/* VFS' acl_permission_check->check_acl will release the refcount */
 	acl = posix_acl_dup(lli->lli_posix_acl);
+	forget_cached_acl(inode, type);
 	spin_unlock(&lli->lli_lock);
 
 	return acl;