proc: remove fs/proc/proc_misc.c

Now that everything was moved to their more or less expected places,
apply rm(1).

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>

include/linux/proc_fs.h

@@ -100,7 +100,6 @@ struct vmcore {
 extern spinlock_t proc_subdir_lock;
 
 extern void proc_root_init(void);
-extern void proc_misc_init(void);
 
 void proc_flush_task(struct task_struct *task);
 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *);