net: libwx: Add sriov api for wangxun nics

Implement sriov_configure interface for wangxun nics in libwx.
Enable VT mode and initialize vf control structure, when sriov
is enabled. Do not be allowed to disable sriov when vfs are
assigned.

Signed-off-by: Mengyuan Lou <mengyuanlou@net-swift.com>
Link: https://patch.msgid.link/81EA45C21B0A98B0+20250408091556.9640-3-mengyuanlou@net-swift.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>