ext4: unexport jbd2_journal_update_superblock

Remove the unused EXPORT_SYMBOL(jbd2_journal_update_superblock).

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index b26c6d9..8207a01 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -68,7 +68,6 @@
 EXPORT_SYMBOL(jbd2_journal_create);
 EXPORT_SYMBOL(jbd2_journal_load);
 EXPORT_SYMBOL(jbd2_journal_destroy);
-EXPORT_SYMBOL(jbd2_journal_update_superblock);
 EXPORT_SYMBOL(jbd2_journal_abort);
 EXPORT_SYMBOL(jbd2_journal_errno);
 EXPORT_SYMBOL(jbd2_journal_ack_err);