CFT: cloned_interfaces and gifconfig in rc.d/netif

Hi,

 The attached patch allows rc.d/netif to create IFs in
 $cloned_interfaces when interface name(s) is specified.  For example,
 when the following lines are in rc.conf:

  cloned_interfaces="bridge0 bridge1"
  ifconfig_bridge0="..."
  ifconfig_bridge1="..."

 The following commands create the interfaces and destroy them.

  # /etc/rc.d/netif start bridge0 bridge1
  # /etc/rc.d/netif stop bridge0 bridge1

 netif cloneup/clonedown does this without the patch, but it cannot
 configure the interfaces and does not support clean teardown.

 Also, routines which handle $gif_interfaces are merged into ones for
 $cloned_interfaces.  ifconfig_gifN and other variants did not work
 with gif interfaces defined in $gif_interfaces.  The patch solves
 this issue.

 Basically there should be no functionality regression for the
 existing configurations.  Can anyone who are using $gif_interfaces
 and/or $cloned_interfaces test this?  I would like to know if there is
 regression or not.

-- Hiroki