msm: vidc: Enable internal buffer size calculation for decoder

Currently buffer size calculation for internal buffers is
disabled. Enable it for decoders as per firmware update.

CRs-Fixed: 2368458
Change-Id: I126e5caa459482b6dfb13dd0bb98da893d0e1c82
Signed-off-by: Vaibhav Deshu Venkatesh <vdeshuve@codeaurora.org>