ARM: tegra: add missing break to fuse initialization code

Add a missing break to the switch in tegra_init_fuse() which determines
which SoC the code is running on. This prevents the Tegra30+ fuse
handling code from running on Tegra20.

Fixes: 3bd1ae57

 ("ARM: tegra: add fuses as device randomness")
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Olof Johansson <olof@lixom.net>