UBI: incorporate LEB offset information

Incorporate the LEB offset information into UBIFS. We'll use this
information in one of the next patches to figure out what are the
max. write size offsets relative to the PEB. So this patch is just
a preparation.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index efc327b..d4b4cb4 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -504,6 +504,7 @@
 
 	c->leb_cnt = c->vi.size;
 	c->leb_size = c->vi.usable_leb_size;
+	c->leb_start = c->di.leb_start;
 	c->half_leb_size = c->leb_size / 2;
 	c->min_io_size = c->di.min_io_size;
 	c->min_io_shift = fls(c->min_io_size) - 1;