drm/msm: Restore error return on invalid fence

When converting to use an idr to map userspace fence seqno values back
to a dma_fence, we lost the error return when userspace passes seqno
that is larger than the last submitted fence.  Restore this check.

Reported-by: Akhil P Oommen <akhilpo@codeaurora.org>
Fixes: a61acbbe

 ("drm/msm: Track "seqno" fences by idr")
Signed-off-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Akhil P Oommen <akhilpo@codeaurora.org>
Link: https://lore.kernel.org/r/20211111192457.747899-3-robdclark@gmail.com


Signed-off-by: Rob Clark <robdclark@chromium.org>