gallium/hud: do not use free() for the free_query_data hook

That confuses Gallium's memory debugging code where CALLOC/MALLOC
must be matched with FREE, not free().

Reviewed-by: Marek Olšák <maraeo@gmail.com>

src/gallium/auxiliary/hud/hud_cpu.c

@@ -116,6 +116,12 @@ query_cpu_load(struct hud_graph *gr)
    }
 }
 
+static void
+free_query_data(void *p)
+{
+   FREE(p);
+}
+
 void
 hud_cpu_graph_install(struct hud_pane *pane, unsigned cpu_index)
 {
@@ -144,7 +150,11 @@ hud_cpu_graph_install(struct hud_pane *pane, unsigned cpu_index)
    }
 
    gr->query_new_value = query_cpu_load;
-   gr->free_query_data = free;
+
+   /* Don't use free() as our callback as that messes up Gallium's
+    * memory debugger.  Use simple free_query_data() wrapper.
+    */
+   gr->free_query_data = free_query_data;
 
    info = gr->query_data;
    info->cpu_index = cpu_index;

src/gallium/auxiliary/hud/hud_fps.c

@@ -60,6 +60,12 @@ query_fps(struct hud_graph *gr)
    }
 }
 
+static void
+free_query_data(void *p)
+{
+   FREE(p);
+}
+
 void
 hud_fps_graph_install(struct hud_pane *pane)
 {
@@ -76,7 +82,11 @@ hud_fps_graph_install(struct hud_pane *pane)
    }
 
    gr->query_new_value = query_fps;
-   gr->free_query_data = free;
+
+   /* Don't use free() as our callback as that messes up Gallium's
+    * memory debugger.  Use simple free_query_data() wrapper.
+    */
+   gr->free_query_data = free_query_data;
 
    hud_pane_add_graph(pane, gr);
 }

src/gallium/auxiliary/hud/hud_private.h

@@ -42,7 +42,7 @@ struct hud_graph {
    char name[128];
    void *query_data;
    void (*query_new_value)(struct hud_graph *gr);
-   void (*free_query_data)(void *ptr);
+   void (*free_query_data)(void *ptr); /**< do not use ordinary free() */
 
    /* mutable variables */
    unsigned num_vertices;