tegra2: Enable instruction cache

Since low-level init is skipped, the instruction cache is never enabled on
Tegra2. This explicitly calls this initialization as soon as the A9 is
initialized.

Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>
diff --git a/board/nvidia/common/board.c b/board/nvidia/common/board.c
index 56850cc..c806a6b 100644
--- a/board/nvidia/common/board.c
+++ b/board/nvidia/common/board.c
@@ -114,6 +114,9 @@
 #ifdef CONFIG_BOARD_EARLY_INIT_F
 int board_early_init_f(void)
 {
+	/* We didn't do this init in start.S, so do it now */
+	cpu_init_cp15();
+
 	/* Initialize essential common plls */
 	clock_early_init();