msm: vidc: Check ion_handle for errors

When ion imports dma buf, it will return negative error number
in the case of failure like bad file number or invalid dma buf file.
check ion_handle for error numbers.

Change-Id: I1ea93161b85deb667cbb6f8515ff7c6943da6e3d
Signed-off-by: Karthikeyan Periasamy <kperiasa@codeaurora.org>
Signed-off-by: Vasantha Balla <vballa@codeaurora.org>