mhi: core: Add API to print system failure reason

mhi_dump_sfr() API parses the RDDM header and scans RDDM segment
for FW crash string in RDDM header. Helper function
mhi_process_sfr() prints the FW crash reason.

Change-Id: I2af202509da16ce03a0567425cbae5b4a0b05ccc
Signed-off-by: Hemant Kumar <hemantk@codeaurora.org>