Well that depends on how you approach it. If you consider the video to be the end product, then one license will cover you need, whether the music is in the intro or the body. But the license will only be good for that video.
If you consider the intro to be your end product you will only need one license for that intro and any video that intro is in. But you will need a license for the music in the main content since this content will change depending on the video. So yes, in this case two licenses would be required.
Depending on your needs, you may want to take one approach or the other.