wifi(implementation): Make a boolean flag atomic

The flag |awaiting_event_loop_termination_| is accessed by multiple
threads, so make it atomic.

Bug: 33552618
Test: Compiles
Change-Id: I5ebe27fe88672565aae0daf34a89616d36f35f90
diff --git a/wifi/1.0/default/wifi_legacy_hal.h b/wifi/1.0/default/wifi_legacy_hal.h
index f79e62a..576dfe6 100644
--- a/wifi/1.0/default/wifi_legacy_hal.h
+++ b/wifi/1.0/default/wifi_legacy_hal.h
@@ -289,7 +289,7 @@
   // Opaque handle to be used for all wlan0 interface specific operations.
   wifi_interface_handle wlan_interface_handle_;
   // Flag to indicate if we have initiated the cleanup of legacy HAL.
-  bool awaiting_event_loop_termination_;
+  std::atomic<bool> awaiting_event_loop_termination_;
   // Flag to indicate if the legacy HAL has been started.
   bool is_started_;
   wifi_system::InterfaceTool iface_tool_;