arm64: dts: ti: k3-j784s4-*: add DP & DP PHY

Add DT nodes for DisplayPort and DisplayPort PHY.
The DP is Cadence MHDP 8546 and the PHY is a
Cadence Torrent PHY with TI WIZ wrapper.
Also add pinmux required for DP HPD.

Signed-off-by: Rahul T R <r-ravikumar@ti.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>