fix: docker workflow for rknn (#16922)

* fix: specify gha runner for rknn

* fix: remove s from platforms

* fix: merge job for rknn

.github/workflows/docker.yml

@@ -129,7 +129,9 @@ jobs:
             runner: ubuntu-24.04-arm
             device: armnn
             suffix: -armnn
-          - platforms: linux/arm64
+            
+          - platform: linux/arm64
+            runner: ubuntu-24.04-arm
             device: rknn
             suffix: -rknn
 
@@ -222,6 +224,8 @@ jobs:
             suffix: -openvino
           - device: armnn
             suffix: -armnn
+          - device: rknn
+            suffix: -rknn
     needs:
       - build_and_push_ml
     steps: