[beken-72xx] Specify keys for OTA packaging

boards/_base/beken-72xx.json

@@ -1,7 +1,13 @@
 {
 	"build": {
 		"f_cpu": "120000000L",
-		"prefix": "arm-none-eabi-"
+		"prefix": "arm-none-eabi-",
+		"bkota": {
+			"encryption": "aes256",
+			"compression": "gzip",
+			"key": "0123456789ABCDEF0123456789ABCDEF",
+			"iv": "0123456789ABCDEF"
+		}
 	},
 	"connectivity": [
 		"wifi",

builder/frameworks/beken-72xx-sdk.py

@@ -7,6 +7,12 @@ from SCons.Script import Builder, DefaultEnvironment
 env = DefaultEnvironment()
 board = env.BoardConfig()
 
+# Install PyCryptodome for OTA packaging with AES
+try:
+    import Cryptodome
+except ImportError:
+    env.Execute("$PYTHONEXE -m pip install pycryptodomex")
+
 ROOT_DIR = join("$SDK_DIR", "beken378")
 APP_DIR = join(ROOT_DIR, "app")
 DRIVER_DIR = join(ROOT_DIR, "driver")