mhi: cntrl: qcom: Add support for fatal error processing

MHI controller needs to handle the fatal error callback issued by the
bus in case reset separation needs to be supported. This state will
occur as a SYS ERROR state with the device being in PBL. Perform a
full power cycle and issue an MHI RESET during power down.

Change-Id: I467943924302ba773c8f6d0c4ad09b51faaeb490
Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>