Revert "network: Check for QOS before blindly using it"

This reverts commit f4db846c.

This patch results in the following error when trying to start
essentially any VM with default network:

unsupported configuration: QOS must be defined for network 'default'

Coverity didn't see that the bandwidth == NULL it complained about in
virNetDevBandwidthPlug was already checked properly in
networkCheckBandwidth, thus causing networkPlugBandwidth to return 0
and finish before a call to virNetDevBandwidthPlug would have been even
made.
Signed-off-by: NErik Skultety <eskultet@redhat.com>
Reviewed-by: NDaniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: NJiri Denemark <jdenemar@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

src/network/bridge_driver.c

@@ -4567,13 +4567,6 @@ networkAllocatePort(virNetworkObjPtr obj,
             return -1;
         }
 
-        if (!port->bandwidth) {
-            virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
-                           _("QOS must be defined for network '%s'"),
-                           netdef->name);
-            return -1;
-        }
-
         if (networkPlugBandwidth(obj, &port->mac, port->bandwidth, &port->class_id) < 0)
             return -1;
         break;
@@ -4640,13 +4633,6 @@ networkAllocatePort(virNetworkObjPtr obj,
                 }
             }
 
-            if (!port->bandwidth) {
-                virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
-                               _("QOS must be defined for network '%s'"),
-                               netdef->name);
-                return -1;
-            }
-
             if (networkPlugBandwidth(obj, &port->mac, port->bandwidth, &port->class_id) < 0)
                 return -1;
             break;