V4L/DVB (5629): Cx88: VP3054 support can't be a module when cx88 is compiled in

If cx88 support is compiled into the kernel while vp3054 is left as a module,
the kernel will fail to link.  Adjust the existing "#if" code in cx88 so
that it won't consider vp3054 to be supported in this case.

It might make sense to move vp3054 selection into the "customisation" menu
instead of a cx88 sub-option (though this is a cx88 feature, there is no extra
chip involved).

It might also make sense to use dvb_attach() to load vp3054 support.

Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>