jbd: Journal block numbers can ever be only 32-bit use unsigned int for them

It does not make sense to store block number for journal as unsigned long
since they can be only 32-bit (because of on-disk format limitation). So
change in-memory structures and variables to use unsigned int instead.

Signed-off-by: Jan Kara <jack@suse.cz>
diff --git a/fs/jbd/checkpoint.c b/fs/jbd/checkpoint.c
index 61f32f3..b0435dd 100644
--- a/fs/jbd/checkpoint.c
+++ b/fs/jbd/checkpoint.c
@@ -456,7 +456,7 @@
 {
 	transaction_t * transaction;
 	tid_t		first_tid;
-	unsigned long	blocknr, freed;
+	unsigned int	blocknr, freed;
 
 	if (is_journal_aborted(journal))
 		return 1;
@@ -502,8 +502,8 @@
 		freed = freed + journal->j_last - journal->j_first;
 
 	jbd_debug(1,
-		  "Cleaning journal tail from %d to %d (offset %lu), "
-		  "freeing %lu\n",
+		  "Cleaning journal tail from %d to %d (offset %u), "
+		  "freeing %u\n",
 		  journal->j_tail_sequence, first_tid, blocknr, freed);
 
 	journal->j_free += freed;