pm: include EIO from errno-base.h

For backwards compatibility, call_platform_enable_wakeup() can return 0
instead of -EIO since we aren't guaranteed to have errno defined.

Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/pm.h

@@ -332,7 +332,7 @@ static inline void dpm_runtime_resume(struct device * dev)
 
 static inline int call_platform_enable_wakeup(struct device *dev, int is_on)
 {
-	return -EIO;
+	return 0;
 }
 
 #endif