arm/tegra: Remove useless entries from ventana_pinmux[]

Some of the entries in ventana_pinmux[] are identical to what's already in
seaboard_pinmux[]. Remove the overrides from the Ventana table.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Olof Johansson <olof@lixom.net>