media: ddbridge: support MaxLinear MXL5xx based cards (MaxS4/8)

This enables MaxS4/S8 and Octopus Max card support in ddbridge by adding
glue code into ddbridge-core, having another PCI ID, and have the LNB IC
control code (and all other MaxS4/8 related code) in ddbridge-maxs8.c
(rather than another ~400 LoC in ddbridge-core.c like it's done in the
original vendor driver package).

Signed-off-by: Daniel Scheller <d.scheller@gmx.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>