cnss2: Handle PCI register rw operation during crash shutdown

During crash shutdown, system is in panic mode and all
interrupts are disabled. Thus when doing CNSS pci register
dump collection do not lock. Use spinlock during normal
operation only.

Change-Id: I82dc531e93c13aa583e8162b8dc7e8866f86c48b
Signed-off-by: Manikandan Mohan <manikand@codeaurora.org>