Build fix:  sa1100/generic.c should already have included <asm/gpio.h>,
but it didn't ... causing a build problem with a recent patch.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>