proc: remove unused argument in proc_pid_lookup()

[[e-mail]: delete "extern" from prototype]
Link: http://lkml.kernel.org/r/20190114195635.GA9372@avx2
Signed-off-by: Zhikang Zhang <[e-mail]>
Signed-off-by: Alexey Dobriyan <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

fs/proc/base.c

···
 	return d_splice_alias(inode, dentry);
 }
 
-struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
+struct dentry *proc_pid_lookup(struct dentry *dentry, unsigned int flags)
 {
 	struct task_struct *task;
 	unsigned tgid;

fs/proc/internal.h

···
 extern void pid_update_inode(struct task_struct *, struct inode *);
 extern int pid_delete_dentry(const struct dentry *);
 extern int proc_pid_readdir(struct file *, struct dir_context *);
-extern struct dentry *proc_pid_lookup(struct inode *, struct dentry *, unsigned int);
+struct dentry *proc_pid_lookup(struct dentry *, unsigned int);
 extern loff_t mem_lseek(struct file *, loff_t, int);
 
 /* Lookups */

fs/proc/root.c

···
 
 static struct dentry *proc_root_lookup(struct inode * dir, struct dentry * dentry, unsigned int flags)
 {
-	if (!proc_pid_lookup(dir, dentry, flags))
+	if (!proc_pid_lookup(dentry, flags))
 		return NULL;
 	
 	return proc_lookup(dir, dentry, flags);