Add Nano R4 (#30)

Resolves #29

Author: dakalamin

boards/nano_r4.json

@@ -0,0 +1,52 @@
+{
+  "build": {
+    "arduino": {
+      "ldscript": "fsp.ld"
+    },
+    "extra_flags": [
+      "-DARDUINO_MINIMA",
+      "-DARDUINO_NANOR4",
+      "-DARDUINO_ARCH_RENESAS_UNO",
+      "-DCFG_TUSB_MCU=OPT_MCU_RAXXX"
+    ],
+    "core": "arduino",
+    "cpu": "cortex-m4",
+    "f_cpu": "48000000L",
+    "hwids": [
+      [
+        "0x2341",
+        "0x0074"
+      ],
+      [
+        "0x2341",
+        "0x0374"
+      ]
+    ],
+    "mcu": "ra4m1",
+    "variant": "NANOR4"
+  },
+  "debug": {
+    "jlink_device": "R7FA4M1AB",
+    "svd_path": "R7FA4M1AB.svd"
+  },
+  "frameworks": [
+    "arduino",
+    "fsp",
+    "cmsis"
+  ],
+  "name": "Arduino Nano R4",
+  "upload": {
+    "maximum_ram_size": 32768,
+    "maximum_size": 262144,
+    "native_usb": true,
+    "protocol": "dfu",
+    "protocols": [
+      "cmsis-dap",
+      "dfu",
+      "jlink"
+    ],
+    "offset_address": "0x4000"
+  },
+  "url": "https://docs.arduino.cc/hardware/nano-r4/",
+  "vendor": "Arduino"
+}

builder/frameworks/fsp.py

@@ -74,7 +74,7 @@
     src_filter.append("+<bsp/mcu/ra4m1>") # Uno R4 (Minima, WiFI)
 else:
     src_filter.append("+<bsp/mcu/ra6m5>") # Portenta
-if board.id in ("uno_r4_minima", "uno_r4_wifi"):
+if board.id in ("uno_r4_minima", "uno_r4_wifi", "nano_r4"):
     src_filter.extend(["+<" + sublib + ">" for sublib in sublibs_uno_r4_x])
     env.Append(CPPPATH=[
         join(FRAMEWORK_DIR, "fsp", "src", "bsp", "mcu", "ra4m1"),

platform.py

@@ -108,7 +108,7 @@ def _add_default_debug_tools(self, board):
                     },
                     "onboard": link in debug.get("onboard_tools", []),
                 }
-            elif link == "cmsis-dap" and board.id in ("uno_r4_wifi", "uno_r4_minima"):
+            elif link == "cmsis-dap" and board.id in ("uno_r4_wifi", "uno_r4_minima", "nano_r4"):
                 hwids = board.get("build.hwids", [["0x2341", "0x1002"]])
                 server_args = [
                     "-s",