[PATCH] Fix sgiioc4 DMA timeout problem with 64KiB s/g elements.

Problem caused by the fact that the code used to only pick the low 16
bits of the bytecount.  That may be how some controllers act on it (byte
count of 0 means 0x10000), but not for this particular hardware.

Signed-off-by: Jeremy Higdon <jeremy@sgi.com>
Acked-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>