soc: qcom: Remove the cpu context and scan dump from watchdog

Remove the scan dump and cpu context information dump table
registration from watchdog driver. As part of unifying the
dump table registration for every subsystem to memory dump
driver, do the necessary driver clean up.

Change-Id: I02ffc5d4dd6839719adcfdbe3436d4e9fabd0981
Signed-off-by: Prasad Sodagudi <psodagud@codeaurora.org>