Removed placeholder prefix

Author: litetex

app/src/main/java/org/schabi/newpipe/util/ServiceHelper.java

@@ -33,15 +33,15 @@ public static int getIcon(final int serviceId) {
             case 0:
                 return R.drawable.ic_smart_display;
             case 1:
-                return R.drawable.ic_placeholder_cloud;
+                return R.drawable.ic_cloud;
             case 2:
                 return R.drawable.ic_placeholder_media_ccc;
             case 3:
                 return R.drawable.ic_placeholder_peertube;
             case 4:
                 return R.drawable.ic_placeholder_bandcamp;
             default:
-                return R.drawable.ic_placeholder_circle;
+                return R.drawable.ic_circle;
         }
     }