msm: camera: sync: Increase number of fences in sync

Some mfhdr usecases require more than 1024 fences because of
delayed request processing and bypass. Increase maximum number
of fences or sync objects to 2048.

CRs-Fixed: 2598592
Change-Id: If11fa2986fce0cd97c14370d29a117230134d6f5
Signed-off-by: Mukund Madhusudan Atre <matre@codeaurora.org>