drm: bridge: dw-hdmi: Reorder functions to prepare for next commit

The next commit will reference structures and functions in a way that
currently requires forward declarations. Reorder the functions to avoid
that. No functional change to the code is performed.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Jose Abreu <joabreu@synopsys.com>
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Link: http://patchwork.freedesktop.org/patch/msgid/20170117082910.27023-9-laurent.pinchart+renesas@ideasonboard.com