All the recent support of Creative boards and onboard audio depend on
PCI, but they can't be trimmed easily even if you build without
CONFIG_PCI, since the quirk is detected dynamically and the code has
many branches with the flag check like spec->quirk type or
spec->use_alt_functions.

This patch makes these checks static for CONFIG_PCI=n case so that the
compiler optimizes out.  The access to flags are replaced with macros
that are replaced with a static value for CONFIG_PCI=n.

The macros look slightly ugly for avoiding compiler warnings wrt
unused variables, and some additional default-case handlings for
another compiler warnings, but the rest are very straightforward
changes.
Signed-off-by: Takashi Iwai <tiwai@suse.de>