ub: uburma add cmd alloc/free key id implementation.

driver inclusion
category: feature
bugzilla: NA
CVE: NA

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Uburma add implementations of handling alloc/free key id cmd from
user layer.

This will make kernel possible to handle urma_alloc_key_id and
urma_free_key_id api in user-layer urma.

Alloc_key_id will finally call ubcore_alloc_key_id. The created key id
will be related to a uobj.
Free_key_id will delete the key-id-related uobj.

Signed-off-by: Guoxin Qian <qianguoxin@huawei.com>
Signed-off-by: Yizhen Fan <fanyizhen@huawei.com>