MIPS: Netlogic: Identify XLP 9XX chip

Adds processor ID of XLP 9XX to asm/cpu.h.  Update netlogic/xlp-hal/xlp.h
to add cpu_is_xlp9xx() and to update cpu_is_xlpii() to support XLP 9XX.

Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Signed-off-by: John Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/6274/