arm64: dts: renesas: ulcb-kf: Add support for TI WL1837

This patch adds description of TI WL1837 and links interfaces
to communicate with the IC, namely the SDIO interface to WLAN.

Signed-off-by: Spyridon Papageorgiou <spapageorgiou@de.adit-jv.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>