PTI feature to allow user to name and mark masterchannel request.

This feature addition provides a new parameter in
pti_request_masterchannel() to allow the user
to provide their own name to mark the request when
the trace is viewed in a PTI SW trace viewer
(like MPTA).  If a name is not provided and
NULL is provided, the 'current' process name is used.
API function header documentation documents this.

Signed-off-by: Jeremy Rocher <rocher.jeremy@gmail.com>
Signed-off-by: J Freyensee <james_p_freyensee@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>