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/fs/proc/base.c b/fs/proc/base.c
index fc5bc27..8b84701 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -2169,7 +2169,7 @@
  */
 static int proc_fd_permission(struct inode *inode, int mask, unsigned int flags)
 {
-	int rv = generic_permission(inode, mask, flags, NULL);
+	int rv = generic_permission(inode, mask, flags);
 	if (rv == 0)
 		return 0;
 	if (task_pid(current) == proc_pid(inode))