dmaengine: idxd: remove gen cap field per spec 1.2 update

mainline inclusion
from mainline-v5.16
commit c5b64b68
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I596WO
CVE: NA

Intel-SIG: commit c5b64b68 dmaengine: idxd: remove gen cap field per spec 1.2 update.
Incremental backporting patches for DSA/IAA on Intel Xeon platform.

--------------------------------

Remove max_descs_per_engine field. The recently released DSA spec 1.2 [1]
has removed this field and made it reserved.

[1]: https://software.intel.com/content/dam/develop/external/us/en/documents-tps/341204-intel-data-streaming-accelerator-spec.pdf



Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163406167978.1303649.1798682437841822837.stgit@djiang5-desk3.ch.intel.com


Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Xiaochen Shen <xiaochen.shen@intel.com>