cpuss_dump: support for register dumping

This feature supports collecting CPUSS register dump
in dump process. It provides interface to user
space to configure the CPUSS registers to be dumped
and per-core register numbers.

Change-Id: I5c1a936d53d6cd7bb32b81513ca22a2d52ef672a
Signed-off-by: qqzhou <qqzhou@codeaurora.org>