[media] gspca_ov519: Fix support for the Terratec Terracam USB Pro

This is a camera with an ov518+ revision 0 bridge + ov7620ae sensor,
which appearently needs different handling then the Trust spacecam 320, which
has an ov518+ revision 2 + ov7620ae sensor. The Terracam USB Pro used to write
this patch has kindly been provided by
Dr. Tilmann Bubeck <t.bubeck@reinform.de>.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>