This addition to the v4l2-api add definitions for the constants and
data structures used for sliced VBI data insertion into MPEG streams triggered
by V4L2_MPEG_STREAM_VBI_FMT_IVTV.  This simply declares what the ivtv and
cx18 drivers and MythTV have already been doing and provides a proper data
structure definition to user space.
Signed-off-by: NAndy Walls <awalls@radix.net>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>