And bring them down first.
This patch is a complement of commit 5e9dd516e2e0 ("add bonding &
xDSL to the list of devices brought up afterwards (#97030,#91399)"),
ensuring that GRE and IPIP tunnels are brought up after base
interfaces are up, and bring down before the underlying interface
goes down.

Before:
[root@rf ~]# service network stop
Shutting down interface eth0:  Device state: 3 (disconnected)
                                                           [  OK  ]
Shutting down interface tunnel0:                           [  OK  ]
Shutting down loopback interface:                          [  OK  ]

After:
[root@rf ~]# service network stop
Shutting down interface tunnel0:                           [  OK  ]
Shutting down interface eth0:  Device state: 3 (disconnected)
                                                           [  OK  ]
Shutting down loopback interface:                          [  OK  ]

Signed-off-by: Rodrigo Freire <rfreire@redhat.com>
 
--- Rodrigo A B Freire .--. - ..--- .-. --- -..