ARM: dts: sync amlogic AXG/GXL/GXM DT from Linux 5.8-rc1

This imports the AXG, GXL & GXM SoC and boards DT changes from the Linux
commit b3a9e3b9622a ("Linux 5.8-rc1").

This change also removes GXL & GXM u-boot.dtsi hacks for USB gadget.

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
diff --git a/arch/arm/dts/meson-axg.dtsi b/arch/arm/dts/meson-axg.dtsi
index aace3d3..8e6281c 100644
--- a/arch/arm/dts/meson-axg.dtsi
+++ b/arch/arm/dts/meson-axg.dtsi
@@ -1735,18 +1735,18 @@
 		};
 
 		sram: sram@fffc0000 {
-			compatible = "amlogic,meson-axg-sram", "mmio-sram";
+			compatible = "mmio-sram";
 			reg = <0x0 0xfffc0000 0x0 0x20000>;
 			#address-cells = <1>;
 			#size-cells = <1>;
 			ranges = <0 0x0 0xfffc0000 0x20000>;
 
-			cpu_scp_lpri: scp-shmem@13000 {
+			cpu_scp_lpri: scp-sram@13000 {
 				compatible = "amlogic,meson-axg-scp-shmem";
 				reg = <0x13000 0x400>;
 			};
 
-			cpu_scp_hpri: scp-shmem@13400 {
+			cpu_scp_hpri: scp-sram@13400 {
 				compatible = "amlogic,meson-axg-scp-shmem";
 				reg = <0x13400 0x400>;
 			};