Original commit message from CVS:
* gst/quicktime/atoms.c:
* gst/quicktime/atoms.h:
* gst/quicktime/descriptors.c:
* gst/quicktime/descriptors.h:
* gst/quicktime/fourcc.h:
* gst/quicktime/ftypcc.h:
* gst/quicktime/gstqtmux.c:
* gst/quicktime/gstqtmux.h:
* gst/quicktime/gstqtmuxmap.c:
* gst/quicktime/gstqtmuxmap.h:
* gst/quicktime/properties.c:
* gst/quicktime/properties.h:
Dual license qtmux LGPL/MIT.  Fixes #564232.