msm: camera: isp: fix overflow during stop axi stream

In dual VFE case, VFE0 and VFE1 will have different behavior
during stoping pix stream. We should disable write master sync
to ensure both VFEs stop as expected.

Change-Id: Ib63b52a948e526e0d2518cb563a4fc4d67340d0f
Signed-off-by: chiz <chiz@codeaurora.org>
CRs-Fixed: 977856