ata: ahci_brcm: Manage reset line during suspend/resume

We were not managing the reset line during suspend/resume, but this
needs to be done to ensure that the controller can exit low power modes
correctly, especially with deep sleep suspend mode that may reset parts
of the logic.

Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>