dt-bindings: phy: Add StarFive JH7110 PCIe PHY

Add StarFive JH7110 SoC PCIe 2.0 PHY dt-binding.
PCIe PHY0 (phy@10210000) can be used as USB 3.0 PHY.

Signed-off-by: Minda Chen <minda.chen@starfivetech.com>
Reviewed-by: Hal Feng <hal.feng@starfivetech.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Roger Quadros <rogerq@kernel.org>
Link: https://lore.kernel.org/r/20230629075115.11934-3-minda.chen@starfivetech.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>