cnss2: Expose PCIe DRV connection status

Interface change to expose PCIe DRV connection status to WLAN
driver so that it is able to suspend/resume based on the status.

Change-Id: If8f706b0eb38f209a5e322b112beb9a95babdcad
Signed-off-by: Yue Ma <yuem@codeaurora.org>