dt-bindings: phy: Add starfive,jh7110-dphy-rx

StarFive SoCs like the jh7110 use a MIPI D-PHY RX controller based on
a M31 IP. Add a binding for it.

Signed-off-by: Changhuang Liang <changhuang.liang@starfivetech.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230718070803.16660-2-changhuang.liang@starfivetech.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>