Fix icon asset

Signed-off-by: Felix Paul Kühne <fkuehne@videolan.org>

vlc-ios/Images.xcassets/AppIcon.appiconset/Contents.json

@@ -15,7 +15,7 @@
     {
       "size" : "40x40",
       "idiom" : "iphone",
-      "filename" : "AppIcon40x40@2x.png",
+      "filename" : "AppIcon40x40@2x-1.png",
       "scale" : "2x"
     },
     {
@@ -57,7 +57,7 @@
     {
       "size" : "40x40",
       "idiom" : "ipad",
-      "filename" : "AppIcon40x40@2x-1.png",
+      "filename" : "AppIcon40x40@2x.png",
       "scale" : "2x"
     },
     {