msm: cpp: Fix mem leak when frame is dropped

When a frame is dropped or during error scenarios frame info
structure is not de-allocated. The fix is to free the frame info
structure after the payload is de-allocated.

Change-Id: Ia804364a01b6bda1d525cd8cc265ecd1aa0b229f
Signed-off-by: Krishnankutty Kolathappilly <kkolatha@codeaurora.org>