crypto: hisilicon - fix strncpy warning with strscpy

Use strscpy to fix the warning
warning: 'strncpy' specified bound 64 equals destination size

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>