msm: camera: isp: Fix CSID acquire in 2PD path

This change allows only one CSID to be acquired in case
of 2PD path as currently only single IFE is supported
for 2PD data.

Change-Id: I8031009cc1646c9b9ffd757aace761ae742a17ca
Signed-off-by: Venkat Chinta <vchinta@codeaurora.org>