V4L/DVB: em28xx: add em286x/tvp5150 reference design

Add support for design which has an em2863/tvp5150 and uses the standard
empia USB ID.  In Sander's case, it was branded as an "Eminent model EM3705"

Thanks to Sander Van Ginkel for testing and help debugging the support.

[mchehab@redhat.com: move it to a vague card number slot (card=29)]
Signed-off-by: Devin Heitmueller <dheitmueller@kernellabs.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>