fix kitti metric deploy (#4227)

ppdet/data/source/category.py

@@ -90,16 +90,19 @@ def get_categories(metric_type, anno_file=None, arch=None):
     elif metric_type.lower() in ['mot', 'motdet', 'reid']:
         return _mot_category()
 
+    elif metric_type.lower() in ['kitti', 'bdd100k']:
+        return _mot_category(category='car')
+
     else:
         raise ValueError("unknown metric type {}".format(metric_type))
 
 
-def _mot_category():
+def _mot_category(category='person'):
     """
     Get class id to category id map and category id
     to category name map of mot dataset
     """
-    label_map = {'person': 0}
+    label_map = {category: 0}
     label_map = sorted(label_map.items(), key=lambda x: x[1])
     cats = [l[0] for l in label_map]