If FileInputStream is not close(), there will be a risk of memory leaks.

Change-Id: I9a0d6100ec26a83fd0e7cb4312246bdd8df28082
diff --git a/protocols/ovsdb/ctl/src/main/java/org/onosproject/ovsdb/controller/impl/TlsParams.java b/protocols/ovsdb/ctl/src/main/java/org/onosproject/ovsdb/controller/impl/TlsParams.java
index 1d09e1d..dfe7fa9 100644
--- a/protocols/ovsdb/ctl/src/main/java/org/onosproject/ovsdb/controller/impl/TlsParams.java
+++ b/protocols/ovsdb/ctl/src/main/java/org/onosproject/ovsdb/controller/impl/TlsParams.java
@@ -143,6 +143,7 @@
             while (dis.read(buffer) > 0) {
                 // nothing to do :)
             }
+            is.close();
             return dis.getMessageDigest().digest();
         } catch (NoSuchAlgorithmException e) {
             log.error("Algorithm SHA1 Not found");