drivers: wifi: remove dependency on NET_SOCKETS_POSIX_NAMES

This change removes references to raw POSIX types and functions,
allowing the drivers to build without NET_SOCKETS_POSIX_NAMES.

After this, the dependency between NET_SOCKETS_OFFLOAD and
NET_SOCKETS_POSIX_NAMES can be removed.

See issue #26033 for additional context

Signed-off-by: Adam Porter <porter.adam@gmail.com>