msm: vidc: Validate userspace buffer count
Makesure the number of buffers count is less than the maximum limit to avoid structure overflow errors. Change-Id: Icf3850de36325637ae43ac95f1c8f0f63e201d31 CRs-fixed: 563694 Signed-off-by: Pachika, Vikas Reddy <vpachi@codeaurora.org>

Signed-off-by: evolutionmod <kernelcraft@gmail.com>