ARM: tegra: Fix hang on reboot

This seems to be a regression in 2.6.37.

We cannot use writel() here since the resulting wmb() calls l2x0_cache_sync()
which uses a spinlock and L1 cache may be off at this point.

http://lists.infradead.org/pipermail/linux-arm-kernel/2011-February/041909.html



Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Colin Cross <ccross@android.com>