Add board definition for upcoming Pololu 3pi+ 2040 Robot (#1259)

Co-authored-by: Paul Grayson <paul@pololu.com>
diff --git a/src/boards/include/boards/pololu_3pi_2040_robot.h b/src/boards/include/boards/pololu_3pi_2040_robot.h
new file mode 100644
index 0000000..a3110cc
--- /dev/null
+++ b/src/boards/include/boards/pololu_3pi_2040_robot.h
@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) 2023 Raspberry Pi (Trading) Ltd.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+// -----------------------------------------------------
+// NOTE: THIS HEADER IS ALSO INCLUDED BY ASSEMBLER SO
+//       SHOULD ONLY CONSIST OF PREPROCESSOR DIRECTIVES
+// -----------------------------------------------------
+
+#ifndef _POLOLU_3PI_2040_ROBOT_H
+#define _POLOLU_3PI_2040_ROBOT_H
+
+// For board detection
+#define POLOLU_3PI_2040_ROBOT
+
+#define PICO_DEFAULT_LED_PIN 25
+#define PICO_BOOT_STAGE2_CHOOSE_W25Q080 1
+#define PICO_FLASH_SPI_CLKDIV 2
+#define PICO_FLASH_SIZE_BYTES (16 * 1024 * 1024)
+
+// All boards have at least the B1 revision
+#define PICO_RP2040_B0_SUPPORTED 0
+
+#endif