V4L/DVB (5375): Add missing VIDEO_CX25840 dep, remove unused VIDEO_TLV320AIC23B dep

VIDEO_CX25840 was missing in the ivtv dependencies. VIDEO_TLV320AIC23B
was removed since it isn't used by ivtv.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>