ARM: dts: at91: at91sam9g15: Style cleanup

- use tags from included dtsi instead of duplicating the hierarchy

There are no differences in the generated .dtbs

Signed-off-by: Uwe Kleine-König <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Alexandre Belloni <[e-mail]>

arch/arm/boot/dts/at91sam9g15.dtsi

···
 / {
 	model = "Atmel AT91SAM9G15 SoC";
 	compatible = "atmel,at91sam9g15", "atmel,at91sam9x5";
+};
 
-	ahb {
-		apb {
-			pinctrl@fffff400 {
-				atmel,mux-mask = <
-				      /*    A         B          C     */
-				       0xffffffff 0xffe0399f 0x00000000  /* pioA */
-				       0x00040000 0x00047e3f 0x00000000  /* pioB */
-				       0xfdffffff 0x00000000 0xb83fffff  /* pioC */
-				       0x003fffff 0x003f8000 0x00000000  /* pioD */
-				      >;
-			};
+&pinctrl {
+	atmel,mux-mask = <
+	      /*    A         B          C     */
+	       0xffffffff 0xffe0399f 0x00000000  /* pioA */
+	       0x00040000 0x00047e3f 0x00000000  /* pioB */
+	       0xfdffffff 0x00000000 0xb83fffff  /* pioC */
+	       0x003fffff 0x003f8000 0x00000000  /* pioD */
+	      >;
+};
 
-			pmc: pmc@fffffc00 {
-				compatible = "atmel,at91sam9g15-pmc", "atmel,at91sam9x5-pmc", "syscon";
-			};
-		};
-	};
+&pmc {
+	compatible = "atmel,at91sam9g15-pmc", "atmel,at91sam9x5-pmc", "syscon";
 };