ARM: dts: koelsch: add HDMI input

Add support in the dts for the HDMI input. Based on the Lager dts
patch from Ulrich Hecht.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
[uli: removed "renesas," prefixes from pfc nodes]
Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>