cleanup floppy.h

AUTO_DMA and FLOPPY_MOTOR_MASK in include/asm-*/floppy.h are dead symbols -
remove them.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>