hns3 udma: support loading and unloading of udma driver.

driver inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I85R2F


CVE: NA

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This patch adds the function of loading and unloading the udma driver.

Signed-off-by: Xincheng Zhu <zhuxincheng2@huawei.com>
Signed-off-by: Weibo Zhao <zhaoweibo3@huawei.com>