dt-bindings: phy: Add QMP USB3+DP PHY for QCS615

dt-bindings: phy: Add QMP USB3+DP PHY for QCS615

Add device tree binding documentation for the Qualcomm QMP USB3+DP PHY
on QCS615 Platform. This PHY supports both USB3 and DP functionality
over USB-C, with PHY mode switching capability. It does not support
combo mode.

Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Xiangxu Yin <xiangxu.yin@oss.qualcomm.com>
Link: https://patch.msgid.link/20251215-add-displayport-support-for-qcs615-platform-v8-1-cbc72c88a44e@oss.qualcomm.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>