Remove acquiring matter context lock for canceling TimerExpiredCallba…

…ck (#26578)

* Remove acquiring matter context lock for canceling TimerExpiredCallback

* Update comment to reflect update to code

src/platform/Linux/bluez/ChipDeviceScanner.cpp

@@ -105,14 +105,10 @@ ChipDeviceScanner::~ChipDeviceScanner()
     StopScan();
 
     // mTimerExpired should only be set to true in the TimerExpiredCallback, which means we are in that callback
-    // right now so there is no need to cancel the timer. Doing so would result in deadlock trying to aquire the
-    // chip stack lock which we already currently have.
+    // right now so there is no need to cancel the timer.
     if (!mTimerExpired)
     {
-        // In case the timeout timer is still active
-        DeviceLayer::PlatformMgr().LockChipStack();
         chip::DeviceLayer::SystemLayer().CancelTimer(TimerExpiredCallback, this);
-        DeviceLayer::PlatformMgr().UnlockChipStack();
     }
 
     g_object_unref(mManager);