userns: Convert ipc to use kuid and kgid where appropriate

- Store the ipc owner and creator with a kuid
- Store the ipc group and the crators group with a kgid.
- Add error handling to ipc_update_perms, allowing it to
  fail if the uids and gids can not be converted to kuids
  or kgids.
- Modify the proc files to display the ipc creator and
  owner in the user namespace of the opener of the proc file.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

init/Kconfig

@@ -925,7 +925,6 @@ config UIDGID_CONVERTED
 
 	# List of kernel pieces that need user namespace work
 	# Features
-	depends on SYSVIPC = n
 	depends on IMA = n
 	depends on EVM = n
 	depends on KEYS = n