crypto: hisilicon - switch to memdup_user_nul()

mainline inclusion
from mainline-master
commit e7662cb9
category: feature
bugzilla: 173981
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e7662cb9e99ef0fd15b8a0dcb3e5d7b32f9812d4



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

Use memdup_user_nul() helper instead of open-coding to
simplify the code.

v1-->v2:
   fixed patch title error
v2-->v3:
   return the actual error

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zou Wei <zou_wei@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Mingqiang Ling <lingmingqiang@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>