soc: qcom: bgdaemon: read data from BG on TWM exit

Separated read data from BG on TWM exit into two part.
BG_FETCH_TWM_DATA will send command to read data from
BG and keep data on bgdeamon and BG_READ_TWM_DATA will
provide data to userspace.

Change-Id: I5af8de7e40ca16216a82c15e9561095364ea8464
Signed-off-by: Ganesh Keethol <gkeethol@codeaurora.org>