Input:
This patch adds dummy gameport_register_port, gameport_unregister_port
and gameport_set_phys functions to gameport.h for the case when a driver
can't use gameport.
This fixes the compilation of some OSS drivers with GAMEPORT=n without
the need to #if inside every single driver.
This patch also removes the non-working and now obsolete SOUND_GAMEPORT.
This patch is also an alternative solution for ALSA drivers with similar
problems (but #if's inside the drivers might have the advantage of
saving some more bytes of gameport is not available).
The only user-visible change is that for GAMEPORT=m the affected OSS
drivers are now allowed to be built statically (but they won't have
gameport support).