x86, debug: gpio_free might sleep

According to the documentation gpio_free should only be called from task
context only.  To make this more explicit add a might sleep to all
implementations.

This patch changes the gpio_free implementations for the x86
architecture.
Signed-off-by: NUwe Kleine-König <ukleinek@informatik.uni-freiburg.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

include/asm-x86/mach-rdc321x/gpio.h

 #ifndef _RDC321X_GPIO_H
 #define _RDC321X_GPIO_H
 
+#include <linux/kernel.h>
+
 extern int rdc_gpio_get_value(unsigned gpio);
 extern void rdc_gpio_set_value(unsigned gpio, int value);
 extern int rdc_gpio_direction_input(unsigned gpio);
@@ -18,6 +20,7 @@ static inline int gpio_request(unsigned gpio, const char *label)
 
 static inline void gpio_free(unsigned gpio)
 {
+	might_sleep();
 	rdc_gpio_free(gpio);
 }