Makefile cannot remove LOCAL_ directories and contents

Fix by having the rm remove the type files typically
copied in for LOCAL_PYVOLTHA or LOCAL_PROTOS

Change-Id: Ica583a5882efbb89e8d4555b8d7416efbe1026fd
diff --git a/python/Makefile b/python/Makefile
index 9e371d0..e094133 100644
--- a/python/Makefile
+++ b/python/Makefile
@@ -64,16 +64,16 @@
 local-protos:
 	mkdir -p local_imports
 ifdef LOCAL_PROTOS
-	rm -f local_imports/voltha-protos/dist
 	mkdir -p local_imports/voltha-protos/dist
+	rm -f local_imports/voltha-protos/dist/*.tar.gz
 	cp ${LOCAL_PROTOS}/dist/*.tar.gz local_imports/voltha-protos/dist/
 endif
 
 local-pyvoltha:
 	mkdir -p local_imports
 ifdef LOCAL_PYVOLTHA
-	rm -f local_imports/pyvoltha/dist
 	mkdir -p local_imports/pyvoltha/dist
+	rm -f local_imports/pyvoltha/dist/*.tar.gz
 	cp ${LOCAL_PYVOLTHA}/dist/*.tar.gz local_imports/pyvoltha/dist/
 endif