build: fix bitmap conversion when !CPU_ALLOC

Commit f1a43a8e missed one side of an #if/#else.

* src/util/processinfo.c (virProcessInfoGetAffinity): Use correct
bitmap operation.
(cherry picked from commit 9038ac65)

src/util/processinfo.c

@@ -161,7 +161,7 @@ realloc:
 
     for (i = 0 ; i < maxcpu ; i++)
         if (CPU_ISSET(i, &mask))
-            VIR_USE_CPU(map, i);
+            ignore_value(virBitmapSetBit(*map, i));
 # endif
 
     return 0;