socket: mark return code with RVAL_FD flag

* net.c (sys_socket): Set RVAL_FD flag in the return code.
* tests/net-yy-accept.awk: Update socket and bind regexps.
* tests/unix-yy-accept.awk: Likewise.
* tests/net-yy-connect.awk: Update socket and connect regexps.
* tests/unix-yy-connect.awk: Likewise.
5 files changed