ata: Add support for the Tegra124 SATA controller

This adds support for the integrated AHCI-compliant Serial ATA
controller present on the NVIDIA Tegra124 system-on-chip.

Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
ARM: tegra: Add options for Tegra AHCI support to tegra_defconfig

This adds ATA, SATA_AHCI and AHCI_TEGRA support to tegra_defconfig
so that the SATA support will be automatically enabled.

Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>