defconfig: Enable camera for 8916

Enable the required compiler directives so that
camera is enabled for 8916 target.

Change-Id: Ic1f5e564ad9e1618b6837778366ae38133169fcd
Signed-off-by: Aditya Jonnalagadda <ajonnala@codeaurora.org>
Signed-off-by: Seemanta Dutta <seemanta@codeaurora.org>