soc: qcom: rpm_master_stat: Add additional debug stats

Adding support to print additional XO sleep related debug stats
the rpm maintains for each of the masters. The additional stats
include xo_count, xo_last_entered_at, xo_last_exited_at, and
xo_accumulated_duration.

CRs-Fixed: 985182
Change-Id: I39d3d234222b6136ab0e68367e13c1276dce61f6
Signed-off-by: Ramakrishnan Ganesh <ramakris@codeaurora.org>