Revert "ARM64: DTS: meson-gxbb: switch ethernet to real clock"

This reverts commit f3abd629, which caused a build regression:

arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi:48:41: fatal error: dt-bindings/clock/gxbb-clkc.h: No such file or directory

We should apply this patch one merge window later, once the clk branch
is merged as well.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi

@@ -45,7 +45,6 @@
 #include <dt-bindings/interrupt-controller/arm-gic.h>
 #include <dt-bindings/gpio/meson-gxbb-gpio.h>
 #include <dt-bindings/reset/amlogic,meson-gxbb-reset.h>
-#include <dt-bindings/clock/gxbb-clkc.h>
 
 / {
 	compatible = "amlogic,meson-gxbb";
@@ -338,7 +337,7 @@ ethmac: ethernet@c9410000 {
 			       0x0 0xc8834540 0x0 0x4>;
 			interrupts = <0 8 1>;
 			interrupt-names = "macirq";
-			clocks = <&clkc CLKID_ETH>;
+			clocks = <&xtal>;
 			clock-names = "stmmaceth";
 			phy-mode = "rgmii";
 			status = "disabled";