msm: vidc: Amend error check conditions on ION APIs

Amend error check conditions appropriately to return
properly from video applications in case of ION API
failures.

Change-Id: Ibe95a8438a66e88b35dbff0af8842ff4b038c5e1
Signed-off-by: Maheshwar Ajja <majja@codeaurora.org>