msm: vidc: update memory limit check based on min_host_count

msm_comm_check_memory_supported is depends on actual_count. Codec2
configures vb2 queues for 64 buffers, but during video usecase, only
limited number of buffers were allocated and same willbe reused from
buffer pool. Only those buffers would be consuming memory. So changed
logic to estimate memory consumption based on min_host_count instead
of actual_count.

Change-Id: I447dee68f8480dad38c285c40af5583f00b91d8f
Signed-off-by: Govindaraj Rajagopal <grajagop@codeaurora.org>