More git-describe debugging.

Signed-off-by: Tim 'mithro' Ansell <tansell@google.com>
diff --git a/open_pdks/build-info.py b/open_pdks/build-info.py
index 5fd8835..d64971d 100755
--- a/open_pdks/build-info.py
+++ b/open_pdks/build-info.py
@@ -64,6 +64,8 @@
         v_str = 'v'+v_str
     versions[k]['version'] = v_str
 
+    assert '-' in v_str, v_str
+    assert v_str.count('-') == 2, v_str
     ver, count, commit = v_str.split('-')
     assert commit.startswith('g'), commit
     commit = commit[1:]