ata: ahci: drop hpriv param from ahci_update_initial_lpm_policy()

There is no need for ahci_update_initial_lpm_policy() to take hpriv as a
parameter, it can easily be derived from the ata_port.

Tested-by: Damien Le Moal <dlemoal@kernel.org>
Tested-by: Jian-Hong Pan <jhp@endlessos.org>
Acked-by: Jian-Hong Pan <jhp@endlessos.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Niklas Cassel <cassel@kernel.org>