ahci: tegra: use regulator_bulk_set_supply_names()

Use the new regulator helper instead of a for loop.

Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>