[core] Split boards as base files

boards/_base/realtek-ambz-2mb.json

@@ -0,0 +1,21 @@
+{
+	"build": {
+		"ldscript_sdk": "rlx8711B-symbol-v02-img2_xip1_2M_cpp.ld",
+		"ldscript_arduino": "rlx8711B-symbol-v02-img2_xip1_2M_cpp.ld",
+		"amb_boot_all": "boot_all_77F7.bin"
+	},
+	"flash": {
+		"boot_xip": "0x000000+0x4000",
+		"boot_ram": "0x004000+0x4000",
+		"system": "0x009000+0x1000",
+		"calibration": "0x00A000+0x1000",
+		"ota1": "0x00B000+0xC5000",
+		"ota2": "0x0D0000+0xC5000",
+		"userdata": "0x195000+0x6A000",
+		"rdp": "0x1FF000+0x1000"
+	},
+	"upload": {
+		"flash_size": 2097152,
+		"maximum_size": 806912
+	}
+}

boards/_base/realtek-ambz.json

@@ -0,0 +1,42 @@
+{
+	"build": {
+		"f_cpu": "125000000L",
+		"amb_flash_addr": "0x08000000"
+	},
+	"connectivity": [
+		"wifi"
+	],
+	"debug": {
+		"protocol": "openocd",
+		"protocols": [
+			"openocd"
+		],
+		"openocd_config": "amebaz.cfg",
+		"gdb_init": [
+			"mem 0x8000000 0x8200000 ro"
+		]
+	},
+	"frameworks": [
+		"realtek-ambz-sdk",
+		"realtek-ambz-arduino"
+	],
+	"upload": {
+		"maximum_ram_size": 262144,
+		"require_upload_port": true,
+		"speed": 1500000,
+		"protocol": "uart",
+		"protocols": [
+			"uart"
+		]
+	},
+	"doc": {
+		"params": {
+			"manufacturer": "Realtek",
+			"series": "AmebaZ",
+			"voltage": "3.0V - 3.6V",
+			"extra": {
+				"Wi-Fi": "802.11 b/g/n"
+			}
+		}
+	}
+}