msm: camera: jpeg: Fix jpeg flush request issue

Jpeg driver enqueue requests in internal command queue
before sending commands to hardware. Flush request is
issued to a pending command which is not in command queue
and with hardware. Flush tries to free this request
leads to a failure.

Fix to handle flush request on internal command
based on request type.

Change-Id: I3e6541328c71c807c5e24bd1660131bd9c9bd55c
Signed-off-by: Suresh Vankadara <svankada@codeaurora.org>