phy: Restrict phy-hi6220-usb to HiSilicon arm64

The HiSilicon Hi6220 USB PHY is available in HiSilicon Hi6220 SoCs only.
Restrict it to HiSilicon arm64, unless compile-testing.
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NKishon Vijay Abraham I <kishon@ti.com>

drivers/phy/Kconfig

@@ -224,6 +224,7 @@ config PHY_MT65XX_USB3
 
 config PHY_HI6220_USB
 	tristate "hi6220 USB PHY support"
+	depends on (ARCH_HISI && ARM64) || COMPILE_TEST
 	select GENERIC_PHY
 	select MFD_SYSCON
 	help