Resolver: fixed format specification.

Patch by Yichun Zhang (agentzh).

src/core/ngx_resolver.c

diff --git a/src/core/ngx_resolver.c b/src/core/ngx_resolver.c
index 54bd384..8f1c2ae 100644
--- a/src/core/ngx_resolver.c
+++ b/src/core/ngx_resolver.c
@@ -1040,7 +1040,7 @@
     nan = (query->nan_hi << 8) + query->nan_lo;
 
     ngx_log_debug6(NGX_LOG_DEBUG_CORE, r->log, 0,
-                   "resolver DNS response %ui fl:%04Xui %ui/%ui/%ui/%ui",
+                   "resolver DNS response %ui fl:%04Xui %ui/%ui/%ud/%ud",
                    ident, flags, nqs, nan,
                    (query->nns_hi << 8) + query->nns_lo,
                    (query->nar_hi << 8) + query->nar_lo);