ARM: kprobes: Add Thumb instruction decoding stubs

Extend arch_prepare_kprobe to support probing of Thumb code. For
the actual decoding of Thumb instructions, stub functions are
added which currently just reject the probe.

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>

diff --cc arch/arm/kernel/Makefile
Simple merge

diff --cc arch/arm/kernel/kprobes-thumb.c
Simple merge

diff --cc arch/arm/kernel/kprobes.c
Simple merge

diff --cc arch/arm/kernel/kprobes.h
Simple merge