Driver core: fix devres_release_all() return value

Every file should include the headers containing the prototypes for
it's global functions.

Since the GNU C compiler is now able to detect that the function 
prototype of devres_release_all() in the header and the actual function 
disagree regarding the return value, this patch also fixes this bug.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Acked-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/base/devres.c b/drivers/base/devres.c
index e1c0730..e8beb8e 100644
--- a/drivers/base/devres.c
+++ b/drivers/base/devres.c
@@ -10,6 +10,8 @@
 #include <linux/device.h>
 #include <linux/module.h>
 
+#include "base.h"
+
 struct devres_node {
 	struct list_head		entry;
 	dr_release_t			release;