icnss: Add icnss code to handle hang event data

When crash happens, FW write crash info into a MSA0 memory
region. The address offset & length of this memory region
is sent to platform driver on MSA Ready indication. The
platform driver calculates the address, generates virtual
address via ioremap, on receiving SMP2P interrupt it copies
the hang event data from MSA0 region to local buffer and
sends the buffer and length to host driver via FW_DOWN Uevent.

Change-Id: I4228e8189cb69d0fbe52fa2e81e340b4eb19f89b
Signed-off-by: Mohammed Siddiq <msiddiq@codeaurora.org>