Add support for 32 bit ioctl on 64 bit systems for synclink_gt

Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NPaul Fulghum <paulkf@microgate.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>