MIPS: Add new AUDIT_ARCH token for the N32 ABI on MIPS64

MIPS: Add new AUDIT_ARCH token for the N32 ABI on MIPS64

A MIPS64 kernel may support ELF files for all 3 MIPS ABIs
(O32, N32, N64). Furthermore, the AUDIT_ARCH_MIPS{,EL}64 token
does not provide enough information about the ABI for the 64-bit
process. As a result of which, userland needs to use complex
seccomp filters to decide whether a syscall belongs to the o32 or n32
or n64 ABI. Therefore, a new arch token for MIPS64/n32 is added so it
can be used by seccomp to explicitely set syscall filters for this ABI.

Signed-off-by: Markos Chandras <[email protected]>
Acked-by: Eric Paris <[email protected]>
Acked-by: Paul Moore <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Ralf Baechle <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: [email protected]
Link: http://sourceforge.net/p/libseccomp/mailman/message/32239040/
Patchwork: https://patchwork.linux-mips.org/patch/6818/
Signed-off-by: Ralf Baechle <[email protected]>