msm: isp: Populate axi data width even in testgen mode

Camif width from camif config needs to be updated even in
case of TESTGEN mode otherwise we request AB/IB bandwidth
as zero.

Change-Id: I818c27e16132885ac449aa757e124d45b3662a6a
Signed-off-by: Sreesudhan Ramakrish Ramkumar <srramku@codeaurora.org>
Signed-off-by: Seemanta Dutta <seemanta@codeaurora.org>