gpio: build fixes

This fixes various gpio-related build errors (mostly potential)
reported in part by Russell King and Uwe Kleine-König.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Arnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/asm-generic/gpio.h

 #ifndef _ASM_GENERIC_GPIO_H
 #define _ASM_GENERIC_GPIO_H
 
+#include <linux/types.h>
+
 #ifdef CONFIG_HAVE_GPIO_LIB
 
+#include <linux/compiler.h>
+
 /* Platforms may implement their GPIO interface with library code,
  * at a small performance cost for non-inlined operations and some
  * extra memory (for code and for per-GPIO table entries).
@@ -74,7 +78,7 @@ struct gpio_chip {
 
 extern const char *gpiochip_is_requested(struct gpio_chip *chip,
 			unsigned offset);
-extern int __init __must_check gpiochip_reserve(int start, int ngpio);
+extern int __must_check gpiochip_reserve(int start, int ngpio);
 
 /* add/remove chips */
 extern int gpiochip_add(struct gpio_chip *chip);

include/linux/gpio.h

@@ -8,6 +8,9 @@
 
 #else
 
+#include <linux/types.h>
+#include <linux/errno.h>
+
 /*
  * Some platforms don't support the GPIO programming interface.
  *