msm: vidc: Handle perf mode configuration

Host will set the Venus firmware in below modes
1. If the load of current video session exceeds
the venus capability, video driver sets power
save mode for that session.
2. If an usecase is recommended to run in power
save mode to get power benefits, video driver
configures the session in power save mode.
3. If any V4L2 client makes an explicit call to
configure the usecase in a certain perf mode,
video driver sets the same to venus firmware,
unless restricted by core capability.

CRs-Fixed: 1106972
Change-Id: Ib8be6c9af1508389edc9cb6444531c6e711b6a11
Signed-off-by: Vikash Garodia <vgarodia@codeaurora.org>
Signed-off-by: Sanjay Singh <sisanj@codeaurora.org>