fiq_debugger: Add fiq_watchdog_triggered api

Dumps registers and stacktrace into console-ramoops when called
from a watchdog fiq.

Change-Id: Ib6fab5a52f670db18e64214d5e4890e8292a749c
Signed-off-by: Arve Hjønnevåg <arve@android.com>
Git-commit: 1b48727337de9e12237583931315cc6d85532415
Git-repo: https://android.googlesource.com/kernel/common.git


Signed-off-by: Ian Maund <imaund@codeaurora.org>