Swap to groovy for loop.

Change-Id: Ic5323b543a84afef10da7e87960802e82087edd9
diff --git a/vars/functions.groovy b/vars/functions.groovy
index 264fc17..f5fa147 100644
--- a/vars/functions.groovy
+++ b/vars/functions.groovy
@@ -63,7 +63,7 @@
     def repoName = nameFromRepoType(repoType, boardName)
     def packageFilenames = findFiles(glob: '**/*.deb')
 
-    for (FileWrapper wrapper : packageFilenames) {
+    for file in packageFilenames {
         sh """
            echo Uploading ${file.path}
            /usr/local/bin/aptly-ctl -C url=http://aptly-api/api \