V4L/DVB (13023): go7007: Merge struct gofh and go declarations

The declarations for struct go7007_file *gofh and struct go7007 *go can
be merged when gofh isn't used by the function.

Signed-off-by: Pete Eberlein <pete@sensoray.com>
Signed-off-by: Douglas Schilling Landgraf <dougsland@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>