soc: qcom: hab: add send/recv total msg count

This stat can be used to determine if there is any
message lost between hab_vchan_send and hab_vchan_recv.

Change-Id: I37be3e0a1359315e213399b9f91b18158006cd3e
Signed-off-by: Rahul Sharma <rahsha@codeaurora.org>
Signed-off-by: Yong Ding <yongding@codeaurora.org>