imx-drm fixes for IPUv3 DC and i.MX5 IPUv3 IC and TVE

- Corrected handling of wait_for_completion_timeout return value
  when disabling IPUv3 DC channels
- Fixed error return value propagation in TVE mode_set
- Fixed IPUv3 register offsets for IC module on i.MX51 and i.MX53

* tag 'imx-drm-fixes-2015-01-28' of git://git.pengutronix.de/git/pza/linux:
  gpu: ipu-v3: Fix IC control register offset
  drm: imx: imx-tve: Check and propagate the errors
  gpu: ipu-v3: wait_for_completion_timeout does not return negative status