Fixed build error on Dockerfile witht the LOCAL_PROTOS or LOCAL_PYVOLTHA flags, while keeping it passing with docker lint

Change-Id: Ia2ef797598c308b58a640e85edc17f47150e30af
diff --git a/python/docker/Dockerfile.ofagent b/python/docker/Dockerfile.ofagent
index d5717ff..52ebaaa 100644
--- a/python/docker/Dockerfile.ofagent
+++ b/python/docker/Dockerfile.ofagent
@@ -42,12 +42,16 @@
 ARG LOCAL_PROTOS
 COPY local_imports/ /local_imports/
 RUN if [ -n "$LOCAL_PYVOLTHA" ] ; then \
-    pip install /local_imports/pyvoltha/dist/*.tar.gz==* ; \
+    PYVOLTHA_PATH=$(ls /local_imports/pyvoltha/dist/) ; \
+    printf "/local_imports/pyvoltha/dist/%s\npyvoltha" "$PYVOLTHA_PATH" > pyvoltha-install.txt ; \
+    pip install -r pyvoltha-install.txt ; \
 fi
 
 RUN if [ -n "$LOCAL_PROTOS" ] ; then \
-    pip install /local_imports/voltha-protos/dist/*.tar.gz==* ; \
-fi
+    PROTOS_PATH=$(ls /local_imports/voltha-protos/dist/) ; \
+    printf "/local_imports/voltha-protos/dist/%s\nvoltha-protos" "$PROTOS_PATH" > protos-install.txt ; \
+    pip install -r protos-install.txt ; \
+ fi
 
 # Bundle app source
 RUN mkdir /ofagent  && \