VOL-2103 - Device reason update modifications

get_device + device_updates are changed by new api device_reason_update.

****Change 15759 and Change 15760  need to be merged before this.

Change-Id: I7e361a11f35f81c42c65433ccac32e4b3e5790a2
diff --git a/python/adapters/brcm_openomci_onu/omci/brcm_mib_download_task.py b/python/adapters/brcm_openomci_onu/omci/brcm_mib_download_task.py
index d159a23..973af86 100644
--- a/python/adapters/brcm_openomci_onu/omci/brcm_mib_download_task.py
+++ b/python/adapters/brcm_openomci_onu/omci/brcm_mib_download_task.py
@@ -177,11 +177,8 @@
             self.log.debug('function-entry')
             self.log.info('perform-download')
 
-            device = yield self._handler.core_proxy.get_device(self.device_id)
-
             if self._handler.enabled and len(self._handler.uni_ports) > 0:
-                device.reason = 'performing-initial-mib-download'
-                yield self._handler.core_proxy.device_update(device)
+                yield self._handler.core_proxy.device_reason_update(self.device_id, 'performing-initial-mib-download')
 
             try:
                 # Lock the UNI ports to prevent any alarms during initial configuration