Fix Mac Bearer when machine has no wifi

This manifested itself for some continuous integration machine, all
regular macs have wireless. In case there is no wifi, we would never
emit updateCompleted().

Change-Id: I1c5b0da6e1d73fef2588beb1796207326d430e26
Reviewed-by: Gabriel de Dietrich <gabriel.dedietrich@digia.com>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Reviewed-by: Lorn Potter <lorn.potter@jollamobile.com>

src/plugins/bearer/corewlan/qcorewlanengine.mm

@@ -573,6 +573,8 @@ void QCoreWlanEngine::doRequestUpdate()
             scanThread->start();
     }
     locker.unlock();
+    if ([wifiInterfaces count] == 0)
+        networksChanged();
     [autoreleasepool release];
 }
 

src/plugins/bearer/corewlan/qcorewlanengine_10_6.mm

@@ -631,6 +631,8 @@ void QCoreWlanEngine::doRequestUpdate()
             scanThread->start();
     }
     locker.unlock();
+    if ([wifiInterfaces count] == 0)
+        networksChanged();
     [autoreleasepool release];
 }