Restrict git describe to tags matching v*

Signed-off-by: Michael Marchetti <mmarchetti@sandvine.com>
diff --git a/setup.py b/setup.py
index 4d4073a..28865c1 100755
--- a/setup.py
+++ b/setup.py
@@ -52,7 +52,7 @@
                'osm_openvim/scripts/get_dhcp_lease.sh']
 
 setup(name=__name,
-      version_command=('git describe', 'pep440-git'),
+      version_command=('git describe --match v*', 'pep440-git'),
       description=__description,
       long_description=__description,
       author=__author,