fix building without --with-debug, introduced in r3328
diff --git a/src/os/unix/ngx_alloc.c b/src/os/unix/ngx_alloc.c
index 860666a..c71a102 100644
--- a/src/os/unix/ngx_alloc.c
+++ b/src/os/unix/ngx_alloc.c
@@ -61,7 +61,7 @@
         p = NULL;
     }
 
-    ngx_log_debug2(NGX_LOG_DEBUG_ALLOC, log, 0,
+    ngx_log_debug3(NGX_LOG_DEBUG_ALLOC, log, 0,
                    "posix_memalign: %p:%uz @%uz", p, size, alignment);
 
     return p;
@@ -80,7 +80,7 @@
                       "memalign(%uz, %uz) failed", alignment, size);
     }
 
-    ngx_log_debug2(NGX_LOG_DEBUG_ALLOC, log, 0,
+    ngx_log_debug3(NGX_LOG_DEBUG_ALLOC, log, 0,
                    "memalign: %p:%uz @%uz", p, size, alignment);
 
     return p;