coresight: csr: Add snapshot of Coresight CSR driver

This is a snapshot of the coresight-cti driver as of msm-4.14
commit '7d42028b'.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: Ie4c87252dfb4e462bdde2175b1af999c891fe555
Signed-off-by: Mulu He <muluhe@codeaurora.org>