uml: get declaration of simple_strtoul

Include linux/kernel.h wherever simple_strtoul is used.  This kills a
compile warning in stderr_console.c and potential ones in the other files.

This also fixes a bunch of style violations in exitcode.c.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/um/drivers/line.c

@@ -3,6 +3,7 @@
  * Licensed under the GPL
  */
 
+#include "linux/kernel.h"
 #include "linux/sched.h"
 #include "linux/slab.h"
 #include "linux/list.h"

arch/um/drivers/stderr_console.c

@@ -1,3 +1,4 @@
+#include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/console.h>
 

arch/um/drivers/ubd_kern.c

@@ -20,6 +20,7 @@
 #define MAJOR_NR UBD_MAJOR
 #define UBD_SHIFT 4
 
+#include "linux/kernel.h"
 #include "linux/module.h"
 #include "linux/blkdev.h"
 #include "linux/hdreg.h"