raylib: fix prime state thread (#36504)

fix

selfdrive/ui/lib/prime_state.py

@@ -33,7 +33,6 @@ class PrimeState:
 
     self._running = False
     self._thread = None
-    self.start()
 
   def _load_initial_state(self) -> PrimeType:
     prime_type_str = os.getenv("PRIME_TYPE") or self._params.get("PrimeType")

selfdrive/ui/ui_state.py

@@ -98,6 +98,7 @@ class UIState:
     return not self.started
 
   def update(self) -> None:
+    self.prime_state.start()  # start thread after manager forks ui
     self.sm.update(0)
     self._update_state()
     self._update_status()