soc: qcom: bgcom: Adds support for BG-RSB events

Adds support for multiple events geenerated by BG.
Parses the event data and sends the event to respective
clients.

Change-Id: If344d8b805475595142afc2be13f584f0107ed78
Signed-off-by: Arjun Singh <arsingh@codeaurora.org>