target/xtensa: linux-user: fix sysv IPC structures

target/xtensa: linux-user: fix sysv IPC structures

- make target_ipc_perm fields match kernel definitions for xtensa;
- add target_semid64_ds with proper order of times and reserved fields
  for little/big endian specific for xtensa;
- add missing reserved fields after time fields to the target_shmid_ds;
- fix types of shm_cpid, shm_lpid and shm_nattch fields of
  target_shmid_ds to match kernel definitions for xtensa.

These changes fix guest ipcs output and fix glibc testsuite tests
sysvipc/test-sysvsem and sysvipc/test-sysvshm.

Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>