/usr/s390x-linux-gnu/include/rpc/ is in libc6-dev-s390x-cross 2.27-3ubuntu1cross1.
This file is owned by root:root, with mode 0o755.
..
/usr/s390x-linux-gnu/include/rpc/auth.h
/usr/s390x-linux-gnu/include/rpc/auth_des.h
/usr/s390x-linux-gnu/include/rpc/auth_unix.h
/usr/s390x-linux-gnu/include/rpc/clnt.h
/usr/s390x-linux-gnu/include/rpc/des_crypt.h
/usr/s390x-linux-gnu/include/rpc/key_prot.h
/usr/s390x-linux-gnu/include/rpc/netdb.h
/usr/s390x-linux-gnu/include/rpc/pmap_clnt.h
/usr/s390x-linux-gnu/include/rpc/pmap_prot.h
/usr/s390x-linux-gnu/include/rpc/pmap_rmt.h
/usr/s390x-linux-gnu/include/rpc/rpc.h
/usr/s390x-linux-gnu/include/rpc/rpc_des.h
/usr/s390x-linux-gnu/include/rpc/rpc_msg.h
/usr/s390x-linux-gnu/include/rpc/svc.h
/usr/s390x-linux-gnu/include/rpc/svc_auth.h
/usr/s390x-linux-gnu/include/rpc/types.h
/usr/s390x-linux-gnu/include/rpc/xdr.h
/usr/s390x-linux-gnu/include/rpcsvc/bootparam.h
/usr/s390x-linux-gnu/include/rpcsvc/bootparam_prot.h
/usr/s390x-linux-gnu/include/rpcsvc/bootparam_prot.x
/usr/s390x-linux-gnu/include/rpcsvc/key_prot.h
/usr/s390x-linux-gnu/include/rpcsvc/key_prot.x
/usr/s390x-linux-gnu/include/rpcsvc/klm_prot.h
/usr/s390x-linux-gnu/include/rpcsvc/klm_prot.x
/usr/s390x-linux-gnu/include/rpcsvc/mount.h
/usr/s390x-linux-gnu/include/rpcsvc/mount.x
/usr/s390x-linux-gnu/include/rpcsvc/nfs_prot.h
/usr/s390x-linux-gnu/include/rpcsvc/nfs_prot.x
/usr/s390x-linux-gnu/include/rpcsvc/nis.h
/usr/s390x-linux-gnu/include/rpcsvc/nis.x
/usr/s390x-linux-gnu/include/rpcsvc/nis_callback.h
/usr/s390x-linux-gnu/include/rpcsvc/nis_callback.x
/usr/s390x-linux-gnu/include/rpcsvc/nis_object.x
/usr/s390x-linux-gnu/include/rpcsvc/nis_tags.h
/usr/s390x-linux-gnu/include/rpcsvc/nislib.h
/usr/s390x-linux-gnu/include/rpcsvc/nlm_prot.h
/usr/s390x-linux-gnu/include/rpcsvc/nlm_prot.x
/usr/s390x-linux-gnu/include/rpcsvc/rex.h
/usr/s390x-linux-gnu/include/rpcsvc/rex.x
/usr/s390x-linux-gnu/include/rpcsvc/rquota.h
/usr/s390x-linux-gnu/include/rpcsvc/rquota.x
/usr/s390x-linux-gnu/include/rpcsvc/rstat.h
/usr/s390x-linux-gnu/include/rpcsvc/rstat.x
/usr/s390x-linux-gnu/include/rpcsvc/rusers.h
/usr/s390x-linux-gnu/include/rpcsvc/rusers.x
/usr/s390x-linux-gnu/include/rpcsvc/sm_inter.h
/usr/s390x-linux-gnu/include/rpcsvc/sm_inter.x
/usr/s390x-linux-gnu/include/rpcsvc/spray.h
/usr/s390x-linux-gnu/include/rpcsvc/spray.x
/usr/s390x-linux-gnu/include/rpcsvc/yp.h
/usr/s390x-linux-gnu/include/rpcsvc/yp.x
/usr/s390x-linux-gnu/include/rpcsvc/yp_prot.h
/usr/s390x-linux-gnu/include/rpcsvc/ypclnt.h
/usr/s390x-linux-gnu/include/rpcsvc/yppasswd.h
/usr/s390x-linux-gnu/include/rpcsvc/yppasswd.x
/usr/s390x-linux-gnu/include/rpcsvc/ypupd.h