ClearCase: Don't show Hijack button for dynamic view

The Hijack button (makeWriteableButton) should only
be shown for snapshot views.

Change-Id: I809981885d18b6057d82f73b5104b0f1041cd255
Reviewed-by: Orgad Shaneh <orgads@gmail.com>
Reviewed-by: Tobias Hunger <tobias.hunger@digia.com>

src/plugins/cvs/cvscontrol.cpp

@@ -69,7 +69,6 @@ bool CvsControl::supportsOperation(Operation operation) const
     case AddOperation:
     case DeleteOperation:
     case AnnotateOperation:
-    case OpenOperation:
         break;
     case MoveOperation:
     case CreateRepositoryOperation:
@@ -82,6 +81,11 @@ bool CvsControl::supportsOperation(Operation operation) const
     return rc;
 }
 
+Core::IVersionControl::OpenSupportMode CvsControl::openSupportMode() const
+{
+    return OpenOptional;
+}
+
 bool CvsControl::vcsOpen(const QString &fileName)
 {
     const QFileInfo fi(fileName);