vidc: Skip unsupported session load in load calculation

Sometimes client may take time to release unsupported sessions,
Skip such unsupported sessions load in load calculation to allow
other sessions.

Change-Id: I9ec35da0a6bba762311876d41933f4fc3d7e6f3e
Signed-off-by: Vasantha Balla <quic_vballa@quicinc.com>