[ARM] 3665/1: crunch: add ptrace support

Patch from Lennert Buytenhek

This patch makes it possible to get/set a task's Crunch state via
the ptrace(2) system call.

Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>