lockdep: output lock_class key instead of address for forward dependency output

The key instead of address of lock_class should be output in
/proc/lockdep when forward dependency is output, because key is
output for lock_class itself as identifier too.

This patch is based on x86/auto-latest branch of git-x86 tree, and has
been tested on x86_64 platform.
Signed-off-by: NHuang Ying <ying.huang@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

kernel/lockdep_proc.c

@@ -139,7 +139,7 @@ static int l_show(struct seq_file *m, void *v)
 
 	list_for_each_entry(entry, &class->locks_after, entry) {
 		if (entry->distance == 1) {
-			seq_printf(m, " -> [%p] ", entry->class);
+			seq_printf(m, " -> [%p] ", entry->class->key);
 			print_name(m, entry->class);
 			seq_puts(m, "\n");
 		}