[media] af9015: move 2nd demod power-up wait different location

We need to wait 2nd demod power-up before download firmware. Move
that wait to more correct location.

Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>