[media] af9005, af9015: use symbolic names for USB id table indices

The af9005_properties and af9015_properties tables make use of USB ids
from the USB id tables with hardcoded indices, as in
"&af9015_usb_table[30]".  Adding new entries before the end breaks
such references, so everyone has had to carefully tiptoe to only add
entries at the end of the list.

In the spirit of "dw2102: use symbolic names for dw2102_table
indices", use C99-style initializers with symbolic names for each
index to avoid this.  In the new regime, properties tables referring
to the USB ids have names like "&af9015_usb_table[CINERGY_T_STICK_RC]"
that do not change meaning when items in the USB id table are
reordered.

Encouraged-by: Mauro Carvalho Chehab <mchehab@redhat.com>

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Acked-by: Luca Olivetti <luca@ventoso.org>
Acked-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>