dt-bindings: ptp: Add amazon,vmclock

dt-bindings: ptp: Add amazon,vmclock

The vmclock device provides a PTP clock source and precise timekeeping
across live migration and snapshot/restore operations.

The binding has a required memory region containing the vmclock_abi
structure and an optional interrupt for clock disruption notifications.

The full spec is at https://uapi-group.org/specifications/specs/vmclock/

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Babis Chalios <bchalios@amazon.es>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Tested-by: Takahiro Itazuri <itazur@amazon.com>
Link: https://patch.msgid.link/20260130173704.12575-4-itazur@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>