update descriptor-packages build process

Change-Id: I937d0897a051b655f9de87f49a88610a37c9297e
Signed-off-by: Mike Marchetti <mmarchetti@sandvine.com>
diff --git a/descriptor-packages/.gitignore b/descriptor-packages/.gitignore
new file mode 100644
index 0000000..0766a22
--- /dev/null
+++ b/descriptor-packages/.gitignore
@@ -0,0 +1,2 @@
+nsd/*/build
+vnfd/*/build