Dan Williams authored May 17, 2013 and Dan Winship committed May 20, 2013

This is really, really old 2007-era code.  Any NMDevice that gets
created is already supported, so there's no reason to have every
device set NM_DEVICE_CAP_NM_SUPPORTED.  For those subclasses that
only set that capability, we can remove the subclass method
entirely.  Next, it turns out that the "type capabilities" code
wasn't used anywhere, so remove that too.  Lastly, "cipsec"
interfaces haven't been used on linux in about 5 years (they
were created by the Cisco binary-only IPSec kernel module for
Cisco VPNs long before vpnc and openswan came around) so we can
remove that code too.