msm: vidc: update max mb/sec load

This change is to clamp a codec session based on SM8150 capability.
SM8150 can support maximum of single 1080p@480fps session or codec
sessions adding upto 1080p@480fps.

CRs-Fixed: 2259123
Change-Id: I87ec9155cb5b1f4746a41871a58f3088900f0665
Signed-off-by: Tapas Kumar Kundu <tkundu@codeaurora.org>