sched/headers: Move the 'init_mm' declaration from <linux/sched.h> to <linux/mm_types.h>

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

include/linux/mm_types.h

@@ -546,6 +546,8 @@ struct mm_struct {
 	struct work_struct async_put_work;
 };
 
+extern struct mm_struct init_mm;
+
 static inline void mm_init_cpumask(struct mm_struct *mm)
 {
 #ifdef CONFIG_CPUMASK_OFFSTACK

include/linux/sched.h

@@ -1782,8 +1782,6 @@ static inline int kstack_end(void *addr)
 extern union thread_union init_thread_union;
 extern struct task_struct init_task;
 
-extern struct   mm_struct init_mm;
-
 extern struct pid_namespace init_pid_ns;
 
 /*