All of the implementations of security hooks that take shmid_kernel only
access shm_perm the struct kern_ipc_perm member. This means the
dependencies of the shm security hooks can be simplified by passing
the kern_ipc_perm member of shmid_kernel..
Making this change will allow struct shmid_kernel to become private to ipc/shm.c.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>