tty: Use the generic RS485 ioctl on CRIS

Use the new general RS485 Linux data structure (introduced by Alan with
commit number c26c56c0) in the Cris
architecture too (currently, Cris still uses the old private data
structure instead of the new one).

Signed-off-by: Claudio Scordino <claudio@evidence.eu.com>
Tested-by: Hinko Kocevar <hinko.kocevar@cetrtapot.si>
Tested-by: Janez Cufer <janez.cufer@cetrtapot.si>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>