Remove extraneous space in Arista prefixlist

When diffing config generated with bgpq4 with config exported from an Arista device, many lines are returned as changed. This is because prefixlist on Arista device use 3 spaces and bgpq4 uses 4 spaces.

printer.c

@@ -1165,7 +1165,7 @@ bgpq4_print_eprefix(struct sx_radix_node *n, void *ff)
 
 	sx_prefix_snprintf(n->prefix, prefix, sizeof(prefix));
 
-	snprintf(seqno, sizeof(seqno), " seq %i", seq++);
+	snprintf(seqno, sizeof(seqno), "seq %i", seq++);
 
 	if (n->isAggregate) {
 		if (n->aggregateLow > n->prefix->masklen) {