disk: add TegraPT support

TegraPT is compatible with EFI part but it can't pass Protective MBR check.
Skip this check if CONFIG_TEGRA_PARTITION is enabled, storage uclass is MMC
and devnum is 0. Note, eMMC on supported devices MUST be aliased to mmc0.

Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>