Fixes ZFS compilation with real secpolicy_vnode_setids_setgids function.

secpolicy_vnode_setids_setgids is called with parameter "gid" which is not defined (as we don't HAVE_KSID).
Previously secpolicy_vnode_setids_setgids was a macro definition to zero so reference to gid variable was removed by the preprocessor.

That block of code also used zfs_fuid_create_cred which didn't have a linux fallback code without KSID.
Copied relevant portions from the function body.

Signed-off-by: Massimo Maggi <massimo@mmmm.it>

module/zfs/zfs_acl.c

@@ -1725,9 +1725,7 @@ zfs_acl_ids_create(znode_t *dzp, int flag, vattr_t *vap, cred_t *cr,
 	int		error;
 	zfs_sb_t	*zsb = ZTOZSB(dzp);
 	zfs_acl_t	*paclp;
-#ifdef HAVE_KSID
 	gid_t		gid;
-#endif /* HAVE_KSID */
 	boolean_t	need_chmod = B_TRUE;
 	boolean_t	inherited = B_FALSE;
 
@@ -1741,7 +1739,6 @@ zfs_acl_ids_create(znode_t *dzp, int flag, vattr_t *vap, cred_t *cr,
 
 	acl_ids->z_fuid = vap->va_uid;
 	acl_ids->z_fgid = vap->va_gid;
-#ifdef HAVE_KSID
 	/*
 	 * Determine uid and gid.
 	 */
@@ -1793,7 +1790,6 @@ zfs_acl_ids_create(znode_t *dzp, int flag, vattr_t *vap, cred_t *cr,
 			}
 		}
 	}
-#endif /* HAVE_KSID */
 
 	/*
 	 * If we're creating a directory, and the parent directory has the

module/zfs/zfs_fuid.c

@@ -488,7 +488,6 @@ zfs_fuid_node_add(zfs_fuid_info_t **fuidpp, const char *domain, uint32_t rid,
 	}
 }
 
-#ifdef HAVE_KSID
 /*
  * Create a file system FUID, based on information in the users cred
  *
@@ -501,6 +500,7 @@ uint64_t
 zfs_fuid_create_cred(zfs_sb_t *zsb, zfs_fuid_type_t type,
     cred_t *cr, zfs_fuid_info_t **fuidp)
 {
+#ifdef HAVE_KSID
 	uint64_t	idx;
 	ksid_t		*ksid;
 	uint32_t	rid;
@@ -540,8 +540,16 @@ zfs_fuid_create_cred(zfs_sb_t *zsb, zfs_fuid_type_t type,
 	zfs_fuid_node_add(fuidp, kdomain, rid, idx, id, type);
 
 	return (FUID_ENCODE(idx, rid));
-}
+#else
+	uid_t		id;
+
+	VERIFY(type == ZFS_OWNER || type == ZFS_GROUP);
+
+	id = (type == ZFS_OWNER) ? crgetuid(cr) : crgetgid(cr);
+
+	return ((uint64_t)id);
 #endif /* HAVE_KSID */
+}
 
 /*
  * Create a file system FUID for an ACL ace