imx-drm probing fix

Commit 950b410dd1ab ("gpu: ipu-v3: Fix imx-ipuv3-crtc module autoloading")
broke probing of the imx-drm driver in the non-modular case because the
unset dev->of_node during probing of imx-ipuv3-crtc would cause the
component matching to fail. This patch patch instead matches against
an of_node pointer stored in platform data, allowing dev->of_node to
be left unset for the platform probed imx-ipuv3-crtc devices.

* tag 'imx-drm-fixes-2016-05-24' of git://git.pengutronix.de/git/pza/linux:
  drm/imx: Match imx-ipuv3-crtc components using device node in platform data