procfs: new helper - PDE_DATA(inode)

The only part of proc_dir_entry the code outside of fs/proc
really cares about is PDE(inode)->data.  Provide a helper
for that; static inline for now, eventually will be moved
to fs/proc, along with the knowledge of struct proc_dir_entry
layout.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

drivers/net/wireless/ray_cs.c

@@ -2778,7 +2778,7 @@ static ssize_t int_proc_write(struct file *file, const char __user *buffer,
 		nr = nr * 10 + c;
 		p++;
 	} while (--len);
-	*(int *)PDE(file_inode(file))->data = nr;
+	*(int *)PDE_DATA(file_inode(file)) = nr;
 	return count;
 }