Fix unbound variable app_def

scripts/fbt/appmanifest.py

@@ -193,6 +193,8 @@ class AppBuildset:
         return self.appmgr.get(app_name).supports_hardware_target(self.hw_target)
 
     def _get_app_depends(self, app_name: str) -> List[str]:
+        app_def = self.appmgr.get(app_name)
+
         # Skip app if its target is not supported by the target we are building for
         if not self._check_if_app_target_supported(app_name):
             self._writer(
@@ -200,7 +202,6 @@ class AppBuildset:
             )
             return []
 
-        app_def = self.appmgr.get(app_name)
         return list(
             filter(
                 self._check_if_app_target_supported,