drm/exynos: mic: Rework initialization

Commit dd8b6803 ("exynos: drm: dsi: Attach in_bridge in MIC driver")
moved Exynos MIC attaching from DSI to MIC driver. However the method
proposed there is incomplete and cannot really work. To properly attach
it to the bridge chain, access to the respective encoder is needed. The
Exynos MIC driver always attaches to the encoder created by the Exynos
DSI driver, so grab it via available helpers for getting access to the
CRTC and encoders. This also requires to change the order of driver
component binding to let DSI to be bound before MIC.

Fixes: dd8b6803 ("exynos: drm: dsi: Attach in_bridge in MIC driver")
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Fixed merge conflict.
Signed-off-by: Inki Dae <inki.dae@samsung.com>