dt-bindings: phy: qcom,qusb2: document sm4250/6115 compatible

This compatible string is for the HS USB PHY on sm4250 and sm6115
platforms.

Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Iskren Chernev <iskren.chernev@gmail.com>
Link: https://lore.kernel.org/r/20210622203240.559979-3-iskren.chernev@gmail.com


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