Remove unnecessary namespace

Change-Id: I69123c1c3ea66595d0a1deafbf2f8705fe58660e
Signed-off-by: Gunnar Mills <gmills@us.ibm.com>
diff --git a/image_manager.cpp b/image_manager.cpp
index 8599196..d4dff1b 100644
--- a/image_manager.cpp
+++ b/image_manager.cpp
@@ -169,7 +169,7 @@
     }
 
     // Untar tarball
-    auto rc = Manager::unTar(tarFilePath, imageDirPath.string());
+    auto rc = unTar(tarFilePath, imageDirPath.string());
     if (rc < 0)
     {
         log<level::ERR>("Error occured during untar");