pdh: Return correct error on allocation failure.
diff --git a/dlls/pdh/pdh_main.c b/dlls/pdh/pdh_main.c
index 8e91caf..9ca174b 100644
--- a/dlls/pdh/pdh_main.c
+++ b/dlls/pdh/pdh_main.c
@@ -1098,6 +1098,8 @@
             }
             heap_free( bufferW );
         }
+        else
+            ret = PDH_MEMORY_ALLOCATION_FAILURE;
     }
 
 done: