coresight: ost: Add snapshot of Coresight OST driver

This is a snapshot of the coresight-cti driver as of msm-4.14
commit '7d42028b99d32ad6ec82aa429378fba0280a1c4a'.byte-cntr: Read 64bit rwp
TMC RWP has two 32bit registers which combine to one 64bit register.
Read correct RWP register in byte counter driver.

Change-Id: I6c0d9368120c1b0bab9bda1fedfad5702b413a61
Signed-off-by: Rama Aparna Mallavarapu <aparnam@codeaurora.org>
Signed-off-by: Mulu He <muluhe@codeaurora.org>