We currently decide whether we need to descend into the subdirs of
drivers/ in drivers/Makefile, but link the resulting objects from
the top-level Makefile.

Making these two decisions at the same time (in drivers/Makefile) cleans
up the top-level Makefile quite a bit.

Link order does not change at all apart from sound/, which is now linked
last.

The patch moves:

	* joystick drivers from drivers/char/joystick to drivers/input/joystick
	* gameport drivers from drivers/char/joystick to drivers/input/gameport
	* serio drivers from drivers/char/joystick to drivers/input/serio

I don't think the joystick drivers should stay in char, because they're
NOT character device drivers (check for register_chrdev, none to be found).

It also fixes build problems with sound driver gameport support.