UBIFS: make minimum fanout 3

UBIFS does not really work correctly when fanout is 2,
because of the way we manage the indexing tree. It may
just become a list and UBIFS screws up.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
diff --git a/fs/ubifs/ubifs-media.h b/fs/ubifs/ubifs-media.h
index bd2121f..a9ecbd9 100644
--- a/fs/ubifs/ubifs-media.h
+++ b/fs/ubifs/ubifs-media.h
@@ -87,7 +87,7 @@
 #define UBIFS_SK_LEN 8
 
 /* Minimum index tree fanout */
-#define UBIFS_MIN_FANOUT 2
+#define UBIFS_MIN_FANOUT 3
 
 /* Maximum number of levels in UBIFS indexing B-tree */
 #define UBIFS_MAX_LEVELS 512