fix: clean up duplicate SoC list and fix RKNN converter for rk3588s

- Remove unused supported_socs variable in rknn.py that duplicated
  the SUPPORTED_RK_SOCS constant from frigate.const
- Add rk3588s to rk3588 mapping in rknn_converter.py to ensure custom
  ONNX model conversion works on RK3588S devices

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

frigate/detectors/plugins/rknn.py

@@ -19,8 +19,6 @@ logger = logging.getLogger(__name__)
 
 DETECTOR_KEY = "rknn"
 
-supported_socs = ["rk3562", "rk3566", "rk3568", "rk3576", "rk3588", "rk3588s"]
-
 supported_models = {
     ModelTypeEnum.yologeneric: "^frigate-fp16-yolov9-[cemst]$",
     ModelTypeEnum.yolonas: "^deci-fp16-yolonas_[sml]$",

frigate/util/rknn_converter.py

@@ -189,13 +189,16 @@ def convert_onnx_to_rknn(
             logger.debug("Could not determine SoC type")
             return False
 
+    # Map rk3588s to rk3588 for RKNN toolkit compatibility
+    target_soc = "rk3588" if soc == "rk3588s" else soc
+
     # Get model config for the specified type
     if model_type not in MODEL_TYPE_CONFIGS:
         logger.debug(f"Unsupported model type: {model_type}")
         return False
 
     config = MODEL_TYPE_CONFIGS[model_type].copy()
-    config["target_platform"] = soc
+    config["target_platform"] = target_soc
 
     # RKNN toolkit requires .onnx extension, create temporary copy if needed
     temp_onnx_path = None