vif command should use interface name to delete them

[Édouard Thuleau]

Actually, to delete a vrouter interface with vif command, we need to use the vif ID instead of its name.
And script need to use workaround like:
     post-down vif --delete $(vif --list | awk '/vif[0-9\/]+[\t ]+ OS: vgw0/ { split($1, arr, "/"); print arr[2];}')

$ ./vif --list
vif0/1 OS: vhost0
        Type:Host HWaddr:00:00:00:00:00:00 IPaddr:0
        Vrf:0 Flags:L3 MTU:1514 Ref:3
        RX packets:0 bytes:0 errors:0
        TX packets:0 bytes:0 errors:0

vif0/3 OS: vgw
        Type:Gateway HWaddr:00:01:00:5e:00:00 IPaddr:0
        Vrf:1 Flags:L3 MTU:1514 Ref:2
        RX packets:0 bytes:0 errors:0
        TX packets:0 bytes:0 errors:0

$ ./vif --delete vif0/1
No such device

$ ./vif --delete vhost0
No such device

$ ./vif --delete 1

$ ./vif --list
vif0/3 OS: vgw
        Type:Gateway HWaddr:00:01:00:5e:00:00 IPaddr:0
        Vrf:1 Flags:L3 MTU:1514 Ref:2
        RX packets:0 bytes:0 errors:0
        TX packets:0 bytes:0 errors:0

[OpenContrail Admin (ci-admin-f)]

Review in progress for https://review.opencontrail.org/27016
Submitter: ajeet vijayvergiya (<email address hidden>)

[OpenContrail Admin (ci-admin-f)]

Reviewed: https://review.opencontrail.org/27016
Committed: http://github.org/Juniper/contrail-vrouter/commit/e64c56b44ff02ebe4fe54b7f7932d12501c75b2f
Submitter: Zuul (<email address hidden>)
Branch: master

commit e64c56b44ff02ebe4fe54b7f7932d12501c75b2f
Author: Ajeet Vijayvergiya <email address hidden>
Date: Wed Dec 7 23:55:48 2016 -0800

vif command should use interface name to delete

Following fixes done
1. vif name passed to interface DELETE netlink message
2. vr_interface_delete function fixed to delete by name or index

Tests done
1. Delete by index
2. Delete by vif name, ex vif0/4350
3. Delete by OS intf name, ex pkt0

Closes-Bug: #1277170

Change-Id: I7d327d2601c241a14578f2a223b8ed9325805297
Signed-off-by: Ajeet Vijayvergiya <email address hidden>