Revert "msm: vidc: Fix check for valid session and generate errors asynchronously"

This reverts commit 001e2c39.
Alternatively the chnage I689dd255681826508069fa86fb5a87f92fc775b5
will resolve the issue.

Change-Id: Iacbd5d1fe04af811377406925f9aa39581442503
Signed-off-by: Maheshwar Ajja <majja@codeaurora.org>