Remove useless checks for NULL before freeing

This patch has been generated by the following Coccinelle semantic
patch:

// Remove useless checks for NULL before freeing
//
// free (NULL) is a no-op, so there is no need to avoid it

@@
expression E;
@@
+ free (E);
+ E = NULL;
- if (unlikely (E != NULL)) {
-   free(E);
(
-   E = NULL;
|
-   E = 0;
)
   ...
- }

@@
expression E;
type T;
@@
+ free ((T) E);
+ E = NULL;
- if (unlikely (E != NULL)) {
-   free((T) E);
(
-   E = NULL;
|
-   E = 0;
)
   ...
- }

@@
expression E;
@@
+ free (E);
- if (unlikely (E != NULL)) {
-   free (E);
- }

@@
expression E;
type T;
@@
+ free ((T) E);
- if (unlikely (E != NULL)) {
-   free ((T) E);
- }

Reviewed-by: Brian Paul <brianp@vmware.com>
diff --git a/src/glx/indirect_vertex_array.c b/src/glx/indirect_vertex_array.c
index 115f755..3f7ab67 100644
--- a/src/glx/indirect_vertex_array.c
+++ b/src/glx/indirect_vertex_array.c
@@ -115,14 +115,10 @@
    struct array_state_vector *arrays = state->array_state;
 
    if (arrays) {
-      if (arrays->stack) {
-         free(arrays->stack);
-         arrays->stack = NULL;
-      }
-      if (arrays->arrays) {
-         free(arrays->arrays);
-         arrays->arrays = NULL;
-      }
+      free(arrays->stack);
+      arrays->stack = NULL;
+      free(arrays->arrays);
+      arrays->arrays = NULL;
       free(arrays);
       state->array_state = NULL;
    }