coresight: abort coresight tracing on kernel crash

Add trace events to control aborting CoreSight trace
dynamically based on module parameter.
Coresight driver will dump any trace present in the current sink
in case we hit a kernel panic, user fault or an undefined instruction.

Change-Id: I668c8cda285250a0b8dcccd2c1d2a8471977ce5c
Signed-off-by: Satyajit Desai <sadesai@codeaurora.org>
Signed-off-by: Rama Aparna Mallavarapu <aparnam@codeaurora.org>