dt-bindings: ata: Convert st,ahci to DT schema

Convert the ST AHCI SATA Controller to DT schema format.

The phy-names changes from "ahci_phy" to "sata-phy" with the inclusion
of ahci-common.yaml. That's an ABI change, but the Linux driver at least
ignores the names. The binding uses "ports-implemented" property, so
including ahci-common.yaml is required.

Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>