ARM: dt: tegra: fix length of pad control and mux registers

The reg property contains <base length> not <base last_offset>. Fix
the length values to be length not last_offset.

Cc: stable@vger.kernel.org
Signed-off-by: Pritesh Raithatha <praithatha@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>