[PATCH] chardev: GPIO for SCx200 & PC-8736x: device minor numbers are unsigned ints

Per kernel headers, device minor numbers are unsigned ints.  Do the same in
this driver.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>