fix to fully view call controls

(were cut at left and right on some devices)

Signed-off-by: Marcel Hibbe <dev@mhibbe.de>

app/src/main/res/layout/call_activity.xml

@@ -140,9 +140,7 @@
         android:animateLayoutChanges="true"
         android:background="@android:color/transparent"
         android:gravity="center"
-        android:orientation="horizontal"
-        android:layout_marginStart="40dp"
-        android:layout_marginEnd="40dp">
+        android:orientation="horizontal">
 
         <com.facebook.drawee.view.SimpleDraweeView
             android:id="@+id/pictureInPictureButton"