soc/tegra: pmc: Update Tegra234 reset sources

Update the tegra234_reset_sources array to contain all reset sources for
Tegra234 and NULL out the entries that do not actually exist.

Signed-off-by: Sandipan Patra <spatra@nvidia.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>