drm/msm: make sure to not queue up recovery more than once

drm/msm: make sure to not queue up recovery more than once

If two fault IRQs arrive in short succession recovery work will be
queued up twice.

When recovery runs a second time it may end up killing an unrelated
context.

Prevent this by masking off interrupts when triggering recovery.

Signed-off-by: Antonino Maniscalco <antomani103@gmail.com>
Reviewed-by: Akhil P Oommen <akhilpo@oss.qualcomm.com>
Patchwork: https://patchwork.freedesktop.org/patch/670023/
Signed-off-by: Rob Clark <robin.clark@oss.qualcomm.com>