MIPS: cpuidle wait instruction state

Defines a macro intended to allow trivial use of the regular MIPS wait
instruction from cpuidle drivers, which may simply invoke the macro
within their array of states.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>

diff --cc arch/mips/include/asm/idle.h
Simple merge

diff --cc arch/mips/kernel/idle.c
Simple merge