Fix crash in DHCPv6 renew, introduced in refactor.
diff --git a/src/rfc3315.c b/src/rfc3315.c
index bf3d2a6..b3bf3cf 100644
--- a/src/rfc3315.c
+++ b/src/rfc3315.c
@@ -798,8 +798,8 @@
 		  }
 		
 		
-		if ((this_context != address6_available(context, req_addr, tagif)) ||
-		    (this_context != address6_valid(context, req_addr, tagif)))
+		if ((this_context = address6_available(context, req_addr, tagif)) ||
+		    (this_context = address6_valid(context, req_addr, tagif)))
 		  {
 		    get_context_tag(&state, this_context);