CLEANUP: ebtree: remove another typo, a wrong initialization in insertion code

(from ebtree 6.0.7)

root_right was wrongly initialized first to <root> which is not the same
type, to be later initialized to root->b[EB_RGHT].

Let's simply remove the wrong and useless initialization.
(cherry picked from commit e63a0c2f56369b52c4d00221d83c2c4569605c06)
diff --git a/ebtree/ebimtree.h b/ebtree/ebimtree.h
index 685e940..b40e490 100644
--- a/ebtree/ebimtree.h
+++ b/ebtree/ebimtree.h
@@ -136,7 +136,7 @@
 	struct ebpt_node *old;
 	unsigned int side;
 	eb_troot_t *troot;
-	eb_troot_t *root_right = root;
+	eb_troot_t *root_right;
 	int diff;
 	int bit;
 	int old_node_bit;