Netd callbacks for socket calls in Bionic

Netd callbacks for socket calls sendto(), sendmsg()
and sendmmsg(). It's controlled by two system properties:

[1] ro.vendor.redirect_socket_calls set once in vendor_init context,
read by libnetd_client. It determines if socket calls are shimmed.

[2] net.redirect_socket_calls.hooked set by System Server, read by
shimmed functions. It determines if shimmed functions dispatch
FwmarkCommands.

Bug: 141611769

Change-Id: I3b4a613469bb2b6c9673219217dab121cf392cd5
3 files changed