[ONOS-4616] YANG grouping linker issues fixed.

Change-Id: I741aa9ad1008c02c9a9f90cc117cd43729132129
diff --git a/utils/yangutils/src/main/java/org/onosproject/yangutils/linker/impl/YangResolutionInfo.java b/utils/yangutils/src/main/java/org/onosproject/yangutils/linker/impl/YangResolutionInfo.java
index 6332a99..26d4cb6 100644
--- a/utils/yangutils/src/main/java/org/onosproject/yangutils/linker/impl/YangResolutionInfo.java
+++ b/utils/yangutils/src/main/java/org/onosproject/yangutils/linker/impl/YangResolutionInfo.java
@@ -696,7 +696,7 @@
              * Check if prefix is null or not, to identify whether to search
              * in import list or include list.
              */
-            if (getRefPrefix() != null && !(getRefPrefix().contentEquals(getCurReferenceResolver().getPrefix()))) {
+            if (getRefPrefix() != null && !getRefPrefix().contentEquals(getCurReferenceResolver().getPrefix())) {
                 if (resolveWithImport()) {
                     return;
                 }