ocfs2: move ip_last_trans to struct ocfs2_caching_info

We have the read side of metadata caching isolated to struct
ocfs2_caching_info, now we need the write side.  This means the journal
functions.  The journal only does a couple of things with struct inode.

This change moves the ip_last_trans field onto struct
ocfs2_caching_info as ci_last_trans.  This field tells the journal
whether a pending journal flush is required.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
diff --git a/fs/ocfs2/uptodate.h b/fs/ocfs2/uptodate.h
index f268273..80dbb1d 100644
--- a/fs/ocfs2/uptodate.h
+++ b/fs/ocfs2/uptodate.h
@@ -61,6 +61,7 @@
 void ocfs2_metadata_cache_init(struct ocfs2_caching_info *ci,
 			       const struct ocfs2_caching_operations *ops);
 void ocfs2_metadata_cache_purge(struct ocfs2_caching_info *ci);
+void ocfs2_metadata_cache_exit(struct ocfs2_caching_info *ci);
 
 u64 ocfs2_metadata_cache_owner(struct ocfs2_caching_info *ci);
 struct super_block *ocfs2_metadata_cache_get_super(struct ocfs2_caching_info *ci);