coresight: add support to read cti data

Add support to read cti data from OF nodes. Devices
can use this data to configure CTIs as part of their
configuration.

Change-Id: I1525f98b064e04534e1f177815866737cab112b2
Signed-off-by: Satyajit Desai <sadesai@codeaurora.org>
Signed-off-by: Rama Aparna Mallavarapu <aparnam@codeaurora.org>