kernel/syscall: Fix if enable Net/socket/iperf but not enable iNet/IPv4.

[jasonbu]

Summary

Fix some case break if we enable Net & local socket & rpmsg socket, but did not enable iNet and ipv6, iNet is not a must have feature in Net, especially Asymmetric Multi-Processing devices.

Impact

After patch, able to open iperf to test rpmsg socket etc.

Testing

CI-test, qemu-arm-v7a ostest