memory: tegra: Remove unused headers inclusions

Tegra210 contains some unused leftover headers, remove them for
consistency.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drivers/memory/tegra/tegra210.c

@@ -6,11 +6,6 @@
  * published by the Free Software Foundation.
  */
 
-#include <linux/of.h>
-#include <linux/mm.h>
-
-#include <asm/cacheflush.h>
-
 #include <dt-bindings/memory/tegra210-mc.h>
 
 #include "mc.h"