[media] v4l2: Update Max supported buffer counts

For usecases like High Speed Recording(HSR), High Frame
Recording(HFR), Video and Camera sub-systems need to exchange
more than 32 buffers. This is needed meet strict timing
requirements and to make sure that no sub-system is starving
for buffers due to latencies in both the SW stacks.

Currently, V4L2 framework supports buffer exchange for only 32
buffers. Hence increase the Max supported buffer counts from 32
to 64.

CRs-Fixed: 2023295
Change-Id: If6173addc94aa18e839884a7b5a534466b1e046e
Signed-off-by: Praneeth Paladugu <ppaladug@codeaurora.org>