arm64: dts: qcom: sc7180: Add USB related nodes

Add nodes for DWC3 USB controller, QMP and QUSB PHYs.

Signed-off-by: Sandeep Maheswaram <sanm@codeaurora.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/1573795421-13989-2-git-send-email-sanm@codeaurora.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>