fixed null pointer in the initial operations

components/device-mgt/org.wso2.carbon.device.mgt.core/src/main/java/org/wso2/carbon/device/mgt/core/service/DeviceManagementProviderServiceImpl.java

@@ -2114,7 +2114,7 @@ public class DeviceManagementProviderServiceImpl implements DeviceManagementProv
         deviceIdentifiers.add(deviceIdentifier);
         if (init != null) {
             List<String> initialOperations = init.getOperations();
-
+            if (initialOperations != null) {
                 for (String str : initialOperations) {
                     CommandOperation operation = new CommandOperation();
                     operation.setEnabled(true);
@@ -2125,15 +2125,18 @@ public class DeviceManagementProviderServiceImpl implements DeviceManagementProv
                                 addOperation(deviceType,
                                              operation, deviceIdentifiers);
                     } catch (OperationManagementException e) {
-                    throw new DeviceManagementException("Unable to find the device with the id: '" + deviceIdentifier.getId(),
+                        throw new DeviceManagementException(
+                                "Unable to find the device with the id: '" + deviceIdentifier.getId(),
                                 e);
                     } catch (InvalidDeviceException e) {
-                    throw new DeviceManagementException("Unable to find the device with the id: '" + deviceIdentifier.getId(),
+                        throw new DeviceManagementException(
+                                "Unable to find the device with the id: '" + deviceIdentifier.getId(),
                                 e);
                     }
                 }
             }
         }
+    }
 
     /**
      * Checks for the default group existence and create group based on device ownership