V4L/DVB: cx25840: Fix composite detection

If CX25840_VIN1_CH1 and the like is used, input is not detected as composite.
Their value is 0x800000XX and CX25840_COMPONENT_ON is 0x80000200. So

   739			else if ((vid_input & CX25840_COMPONENT_ON) == 0)

this condition never be true.

Signed-off-by: Kusanagi Kouichi <slash@ac.auone-net.jp>
Reviewed-by: Andy Walls <awalls@radix.net>
Acked-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>