Add compat shim part missed at r305197.

This fixes compatibility between old kernel and new ZFS tools.
It seems to be tradition to forget it. :(

PR:		221112
MFC after:	3 days

cddl/contrib/opensolaris/lib/libzfs/common/libzfs_compat.c

@@ -74,6 +74,9 @@ zcmd_ioctl(int fd, int request, zfs_cmd_t *zc)
 
 	if (zfs_ioctl_version >= ZFS_IOCVER_DEADMAN) {
 		switch (zfs_ioctl_version) {
+		case ZFS_IOCVER_INLANES:
+			cflag = ZFS_CMD_COMPAT_INLANES;
+			break;
 		case ZFS_IOCVER_RESUME:
 			cflag = ZFS_CMD_COMPAT_RESUME;
 			break;