msm: vidc: Do not consider clock for inactive session

Video sessions may go into pause state or remain inactive
as per the client requirement. Clock calculation should
ignore the clock required for such session and do not
include it in the total required clock vote.

Change-Id: I41dce9f47208ef33244b754a076550a0b4b830f9
Signed-off-by: Vikash Garodia <vgarodia@codeaurora.org>