accel/ivpu: Implement warm boot flow for NPU6 and unify boot handling

accel/ivpu: Implement warm boot flow for NPU6 and unify boot handling

Starting from NPU6, the driver can pass boot parameters address through
the AON retention register and toggle between cold/warm boot types using
the boot_type parameter, while setting the cold boot entry point in both
cases.

Refactor the existing cold/warm boot handling to be consistent with the
new NPU6 boot flow requirements and still maintain compatibility with
older boot flows.

This will allow firmware to remove support for legacy warm boot starting
from NPU6.

Fixes: 550f4dd2cedd ("accel/ivpu: Add support for Nova Lake's NPU")
Signed-off-by: Karol Wachowski <karol.wachowski@linux.intel.com>
Reviewed-by: Jeff Hugo <jeff.hugo@oss.qualcomm.com>
Reviewed-by: Andrzej Kacprowski <andrzej.kacprowski@linux.intel.com>
Signed-off-by: Maciej Falkowski <maciej.falkowski@linux.intel.com>
Link: https://patch.msgid.link/20251230142116.540026-1-maciej.falkowski@linux.intel.com