media: sound, isapnp: allow building more drivers with COMPILE_TEST

Drivers that depend on ISAPNP currently can't be built with
COMPILE_TEST. However, looking at isapnp.h, there are already
stubs there to allow drivers to include it even when isa
PNP is not supported.

So, remove such dependencies when COMPILE_TEST.

Acked-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>