ARM: tegra: Enable EXT4 for Tegra

ARM: tegra: Enable EXT4 for Tegra

After commit d6ace46c82fd ("ext4: remove obsolete EXT3 config options")
was added, when using the 'tegra_defconfig' kernel configuration,
mounting an MMC device on Tegra20, Tegra30 and Tegra124 boards is
failing with "unknown filesystem type 'ext4'". Fix this by updating the
'tegra_defconfig' to use the EXT4 config options and remove the
obselete EXT2/3 options.

Fixes: d6ace46c82fd ("ext4: remove obsolete EXT3 config options")
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>