ath10k: Support firmware crash-by-assert.

10.1 firmware does not have an official way to
cause assert on purpose, but it can be done with
carefully crafted WMI command.  This is a different
kind of crash from the 'hard' crash, which is
a bad memory dereference.

Different crashes decode in different manners, so
this will help the crash-report testing as well as
offer better ways to test firmware failure and
recovery.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>