Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Remove some unneeded spaces from the __sym_compat() macro, since newer
versions of gas are more fussy about spaces surrounding '@' signs in
versioned symbol names.

Change the ABI of some of the structures used by the SYSV IPC API:
- The uid/cuid members of struct ipc_perm are now uid_t instead of unsigned
short.
- The gid/cgid members of struct ipc_perm are now gid_t instead of unsigned
short.
- The mode member of struct ipc_perm is now mode_t instead of unsigned short
(this is merely a style bug).
- The rather dubious padding fields for ABI compat with SV/I386 have been
removed from struct msqid_ds and struct semid_ds.
- The shm_segsz member of struct shmid_ds is now a size_t instead of an
int. This removes the need for the shm_bsegsz member in struct
shmid_kernel and should allow for complete support of SYSV SHM regions
>= 2GB.
- The shm_nattch member of struct shmid_ds is now an int instead of a
short.
- The shm_internal member of struct shmid_ds is now gone. The internal
VM object pointer for SHM regions has been moved into struct
shmid_kernel.
- The existing __semctl(), msgctl(), and shmctl() system call entries are
now marked COMPAT7 and new versions of those system calls which support
the new ABI are now present.
- The new system calls are assigned to the FBSD-1.1 version in libc. The
FBSD-1.0 symbols in libc now refer to the old COMPAT7 system calls.
- A simplistic framework for tagging system calls with compatibility
symbol versions has been added to libc. Version tags are added to
system calls by adding an appropriate __sym_compat() entry to
src/lib/libc/incldue/compat.h. [1]

PR: kern/16195 kern/113218 bin/129855
Reviewed by: arch@, rwatson
Discussed with: kan, kib [1]