accel/habanalabs: add NVMe Direct I/O (HLDIO) infrastructure

accel/habanalabs: add NVMe Direct I/O (HLDIO) infrastructure

Introduce NVMe Direct I/O (HLDIO) infrastructure to support
peer‑to‑peer DMA in the habanalabs driver. This adds internal helpers
and data structures to enable direct transfers between NVMe storage
and device memory.

The feature is built only when CONFIG_HL_HLDIO is enabled. A debugfs
interface is also provided for functional validation.

Signed-off-by: Konstantin Sinyuk <konstantin.sinyuk@intel.com>
Reviewed-by: Farah Kassabri <farah.kassabri@intel.com>
Reviewed-by: Koby Elbaz <koby.elbaz@intel.com>
Signed-off-by: Koby Elbaz <koby.elbaz@intel.com>