jbd2: add drop_transaction/update_superblock_end tracepoints

This patch adds trace_jbd2_drop_transaction and
trace_jbd2_update_superblock_end because there are similar tracepoints
in jbd and they are needed in jbd2 as well.

Reviewed-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

diff --git a/fs/jbd2/checkpoint.c b/fs/jbd2/checkpoint.c
index d49d202..453c906 100644
--- a/fs/jbd2/checkpoint.c
+++ b/fs/jbd2/checkpoint.c
@@ -797,5 +797,7 @@
 	J_ASSERT(journal->j_committing_transaction != transaction);
 	J_ASSERT(journal->j_running_transaction != transaction);
 
+	trace_jbd2_drop_transaction(journal, transaction);
+
 	jbd_debug(1, "Dropping transaction %d, all done\n", transaction->t_tid);
 }