v3d: Fix a leak of the transfer helper on screen destroy.

Fixes: 7a30517cce ("broadcom/vc5: Start adding support for rendering to Z32F_S8X24_UINT.")

src/gallium/drivers/v3d/v3d_screen.c

@@ -32,6 +32,7 @@
 #include "util/u_format.h"
 #include "util/u_hash_table.h"
 #include "util/u_screen.h"
+#include "util/u_transfer_helper.h"
 #include "util/ralloc.h"
 
 #include <xf86drm.h>
@@ -74,6 +75,7 @@ v3d_screen_destroy(struct pipe_screen *pscreen)
                 v3d_simulator_destroy(screen);
 
         v3d_compiler_free(screen->compiler);
+        u_transfer_helper_destroy(pscreen->transfer_helper);
 
         close(screen->fd);
         ralloc_free(pscreen);