msm: vidc: Update input buffer counts in set format

Input buffer counts, ie Dec Bitstream and Enc Yuv,
depend on input resolution. Hence they should be recalculated
in set format. Stale values can result in excess memory usage.

CRs-Fixed: 2548727
Change-Id: I57c87270a6613da290f14484897cef16e964e27a
Signed-off-by: Chinmay Sawarkar <chinmays@codeaurora.org>