travis: Install python-sphinx

This will ensure the recently added 'check-docs' target will get run as
part of Travis.

Signed-off-by: Stephen Finucane <stephen@that.guru>
Signed-off-by: Ben Pfaff <blp@ovn.org>

diff --git a/.travis.yml b/.travis.yml
index 90fc6995b22987f4850f2abb02faef7d8eecd2e2..d071e2146467f091176a7c9b33d5590446198d6c 100644 (file)
--- a/.travis.yml
+++ b/.travis.yml
@@ -15,6 +15,7 @@ addons:
       - llvm-dev
       - libjemalloc1
       - libjemalloc-dev
+      - python-sphinx
 
 before_install: ./.travis/${TRAVIS_OS_NAME}-prepare.sh