fixes to catch proper netconf exception

- part of ONOS-7020

Change-Id: I55c02ca9fdb97f1ae12b4e3d7b76da565f9da741
diff --git a/drivers/netconf/src/main/java/org/onosproject/drivers/netconf/NetconfConfigGetter.java b/drivers/netconf/src/main/java/org/onosproject/drivers/netconf/NetconfConfigGetter.java
index 2739872..a353c28 100644
--- a/drivers/netconf/src/main/java/org/onosproject/drivers/netconf/NetconfConfigGetter.java
+++ b/drivers/netconf/src/main/java/org/onosproject/drivers/netconf/NetconfConfigGetter.java
@@ -23,10 +23,9 @@
 import org.onosproject.net.driver.DriverHandler;
 import org.onosproject.netconf.DatastoreId;
 import org.onosproject.netconf.NetconfController;
+import org.onosproject.netconf.NetconfException;
 import org.slf4j.Logger;
 
-import java.io.IOException;
-
 import static org.slf4j.LoggerFactory.getLogger;
 
 /**
@@ -57,7 +56,7 @@
                     get(ofDeviceId).
                     getSession().
                     getConfig(DatastoreId.datastore(type));
-        } catch (IOException e) {
+        } catch (NetconfException e) {
             log.error("Configuration could not be retrieved {}",
                       e.getMessage());
         }