phy: sun50i-usb3: Add a driver for the H6 USB3 PHY

This driver is needed for XHCI to work on the Allwinner H6 SoC. The
driver is copied from Linux v5.10.

Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
diff --git a/drivers/phy/allwinner/Kconfig b/drivers/phy/allwinner/Kconfig
index dba3bae..6bfb79c 100644
--- a/drivers/phy/allwinner/Kconfig
+++ b/drivers/phy/allwinner/Kconfig
@@ -11,3 +11,11 @@
 
 	  This driver controls the entire USB PHY block, both the USB OTG
 	  parts, as well as the 2 regular USB 2 host PHYs.
+
+config PHY_SUN50I_USB3
+	bool "Allwinner sun50i USB3 PHY driver"
+	depends on ARCH_SUNXI
+	select PHY
+	help
+	  Enable this to support the USB3 transceiver that is part of
+	  Allwinner sun50i SoCs.