f2fs: pass checkpoint reason on roll-forward recovery

This patch adds CP_RECOVERY to remain recovery information for checkpoint.
And, it makes sure writing checkpoint in this case.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 053361a..c06a25e 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -103,6 +103,7 @@
 	CP_UMOUNT,
 	CP_FASTBOOT,
 	CP_SYNC,
+	CP_RECOVERY,
 	CP_DISCARD,
 };