FreeBSD: Use SET_ERROR to trace xattr name errors

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Signed-off-by: Ryan Moeller <ryan@iXsystems.com>
Closes #11997

module/os/freebsd/zfs/zfs_vnops_os.c

@@ -5250,10 +5250,10 @@ zfs_create_attrname(int attrnamespace, const char *name, char *attrname,
 
 	/* We don't allow '/' character in attribute name. */
 	if (strchr(name, '/') != NULL)
-		return (EINVAL);
+		return (SET_ERROR(EINVAL));
 	/* We don't allow attribute names that start with "freebsd:" string. */
 	if (strncmp(name, "freebsd:", 8) == 0)
-		return (EINVAL);
+		return (SET_ERROR(EINVAL));
 
 	bzero(attrname, size);
 
@@ -5278,11 +5278,11 @@ zfs_create_attrname(int attrnamespace, const char *name, char *attrname,
 		break;
 	case EXTATTR_NAMESPACE_EMPTY:
 	default:
-		return (EINVAL);
+		return (SET_ERROR(EINVAL));
 	}
 	if (snprintf(attrname, size, "%s%s%s%s", prefix, namespace, suffix,
 	    name) >= size) {
-		return (ENAMETOOLONG);
+		return (SET_ERROR(ENAMETOOLONG));
 	}
 	return (0);
 }