kill check_acl callback of generic_permission()

its value depends only on inode and does not change; we might as
well store it in ->i_op->check_acl and be done with that.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 8c84ed9..0c15d5e 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2187,8 +2187,7 @@
 #endif
 extern int notify_change(struct dentry *, struct iattr *);
 extern int inode_permission(struct inode *, int);
-extern int generic_permission(struct inode *, int, unsigned int,
-		int (*check_acl)(struct inode *, int, unsigned int));
+extern int generic_permission(struct inode *, int, unsigned int);
 
 static inline bool execute_ok(struct inode *inode)
 {