boards: raspberrypi: rpi_pico: Include default partitions

Include sysbuild 2M partitions for rpi_pico boards; and
choose to use the slot0_partition as the code-partition.

Signed-off-by: John Lin <john.lin@beechwoods.com>

Author: jlbwoods

boards/raspberrypi/rpi_pico/rpi_pico-common.dtsi

@@ -12,6 +12,7 @@
 
 #include <zephyr/dt-bindings/i2c/i2c.h>
 
+#include <raspberrypi/partitions_2M_sysbuild.dtsi>
 
 / {
 	chosen {
@@ -20,7 +21,7 @@
 		zephyr,flash-controller = &ssi;
 		zephyr,console = &uart0;
 		zephyr,shell-uart = &uart0;
-		zephyr,code-partition = &code_partition;
+		zephyr,code-partition = &slot0_partition;
 	};
 
 	aliases {
@@ -64,29 +65,6 @@
 
 &flash0 {
 	reg = <0x10000000 DT_SIZE_M(2)>;
-
-	partitions {
-		compatible = "fixed-partitions";
-		#address-cells = <1>;
-		#size-cells = <1>;
-
-		/* Reserved memory for the second stage bootloader */
-		second_stage_bootloader: partition@0 {
-			label = "second_stage_bootloader";
-			reg = <0x00000000 0x100>;
-			read-only;
-		};
-
-		/*
-		 * Usable flash. Starts at 0x100, after the bootloader. The partition
-		 * size is 2MB minus the 0x100 bytes taken by the bootloader.
-		 */
-		code_partition: partition@100 {
-			label = "code-partition";
-			reg = <0x100 (DT_SIZE_M(2) - 0x100)>;
-			read-only;
-		};
-	};
 };
 
 &uart0 {