[VOL-3590] Synchronizing read ans subsequent write to the pending Meters map to avoid duplicate meters

Change-Id: I7c08a642dd7183f5bed2da86f59f53a30865790a
diff --git a/app/src/main/java/org/opencord/olt/impl/Olt.java b/app/src/main/java/org/opencord/olt/impl/Olt.java
index d572657..3323480 100644
--- a/app/src/main/java/org/opencord/olt/impl/Olt.java
+++ b/app/src/main/java/org/opencord/olt/impl/Olt.java
@@ -797,11 +797,10 @@
         }
     }
     private void checkAndCreateDevMeter(DeviceId deviceId, BandwidthProfileInformation bwpInfo) {
-        if (oltMeterService.isMeterPending(deviceId, bwpInfo)) {
-            log.debug("Meter is already pending {} on device {}", bwpInfo, deviceId);
+        //If false the meter is already being installed, skipping installation
+        if (!oltMeterService.checkAndAddPendingMeter(deviceId, bwpInfo)) {
             return;
         }
-        oltMeterService.addToPendingMeters(deviceId, bwpInfo);
         createMeter(deviceId, bwpInfo);
     }