net: spnic: initial commit the common module of Ramaxel NIC driver

Ramaxel inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I4CBDP


CVE: NA

This initial commit contains Ramaxel's spnic common module

Signed-off-by: Yanling Song <songyl@ramaxel.com>
Reviewed-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>