dt-bindings: phy: qcom,qusb2: Add bindings for QCS615

Update dt-bindings to add QCS615 to QUSB2 Phy list.

Signed-off-by: Krishna Kurapati <quic_kriskura@quicinc.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20241014084432.3310114-3-quic_kriskura@quicinc.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>