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>
diff --git a/drivers/parisc/led.c b/drivers/parisc/led.c
index d4d800c..b482431 100644
--- a/drivers/parisc/led.c
+++ b/drivers/parisc/led.c
@@ -172,14 +172,14 @@
 
 static int led_proc_open(struct inode *inode, struct file *file)
 {
-	return single_open(file, led_proc_show, PDE(inode)->data);
+	return single_open(file, led_proc_show, PDE_DATA(inode));
 }
 
 
 static ssize_t led_proc_write(struct file *file, const char *buf,
 	size_t count, loff_t *pos)
 {
-	void *data = PDE(file_inode(file))->data;
+	void *data = PDE_DATA(file_inode(file));
 	char *cur, lbuf[32];
 	int d;