fsnotify(): constify 'data'

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
index d357041..e6ea675 100644
--- a/include/linux/fsnotify_backend.h
+++ b/include/linux/fsnotify_backend.h
@@ -245,7 +245,7 @@
 /* called from the vfs helpers */
 
 /* main fsnotify call to send events */
-extern int fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is,
+extern int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is,
 		    const unsigned char *name, u32 cookie);
 extern int __fsnotify_parent(struct path *path, struct dentry *dentry, __u32 mask);
 extern void __fsnotify_inode_delete(struct inode *inode);
@@ -357,7 +357,7 @@
 
 #else
 
-static inline int fsnotify(struct inode *to_tell, __u32 mask, void *data, int data_is,
+static inline int fsnotify(struct inode *to_tell, __u32 mask, const void *data, int data_is,
 			   const unsigned char *name, u32 cookie)
 {
 	return 0;