vc4_bufmgr: Remove duplicative VC definition

This is already defined in
  src/broadcom/cle/v3d_packet_helpers.h:42:9

And was causing build issues in AOSP when building with mmma

Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4175>

src/gallium/drivers/vc4/vc4_bufmgr.c

@@ -36,14 +36,6 @@
 #include "vc4_context.h"
 #include "vc4_screen.h"
 
-#ifdef HAVE_VALGRIND
-#include <valgrind.h>
-#include <memcheck.h>
-#define VG(x) x
-#else
-#define VG(x)
-#endif
-
 static bool dump_stats = false;
 
 static void