Add support for video cds

[bitsgalore]

Catalog search:

extent any "Video-CD"

Returns 8 hits. These discs follow the CD-i Bridge layout and XA mode. See:

https://en.wikipedia.org/wiki/Video_CD

Since the tracks on a video CD mix Form 1 (2048 bytes user data) and Form 2 (2324 bytes user data), probably best to make a raw image (see also email IsoBuster author on CD-i).