drm: bridge: dw-hdmi: Move IRQ and IO resource allocation to common code

There's no need to duplicate identical code in multiple drivers (two at
the moment, one more to come soon). Move it to the dw-hdmi core where it
can be shared. If resource allocation ever becomes device-specific later
we'll always have the option of splitting it out again.

While it at pass the platform device to the bind function to avoid
having to cast struct device to struct platform_device.

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/20170117082910.27023-8-laurent.pinchart+renesas@ideasonboard.com