[PATCH] I2O: Limit max sector workaround for Promise controllers

Set max sectors to 256 for Promise controllers.

Signed-off-by: Markus Lidel <Markus.Lidel@shadowconnect.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>