Fix libvpx config tests

It'll never pass unless the code is valid C++.

Change-Id: I8b4ab98c34b94afd94b6fffd15516ec82d79bf17
Reviewed-by: Jüri Valdmann <juri.valdmann@qt.io>

config.tests/libvpx/libvpx.cpp

@@ -34,7 +34,7 @@ int main(int, char **)
     // Members added (as ints) by
     // https://chromium-review.googlesource.com/c/webm/libvpx/+/798222
     // And changed to int arrays by
-    /  https://chromium-review.googlesource.com/c/webm/libvpx/+/879089
+    //  https://chromium-review.googlesource.com/c/webm/libvpx/+/879089
     pkt.data.frame.width[0] = 0u;
     pkt.data.frame.height[0] = 0u;
     return 0;