msm: vidc: Remove session_suspend and session_resume hooks in HFI

session_suspend and _resume aren't used anywhere and there's no usecase
to use them in the future.  Hence, get rid of dead code.

Change-Id: Ide8cb7d1ad13f0ec851bedd70cbfc050e52f1876
Signed-off-by: Deva Ramasubramanian <dramasub@codeaurora.org>