Travis: don't test with both gcc and clang
In practice, we hardly ever get different outcomes, so there is no
gain in running tests with different compilers.
Experimentally, with the builds and tests we currently do and with the
compiler versions on a Travis Ubuntu 16.04, gcc jobs are significantly
faster than clang jobs (13 min vs 24 min). So use gcc.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/.travis.yml b/.travis.yml
index 0685bdb..11d679c 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,7 +1,5 @@
language: c
-compiler:
-- clang
-- gcc
+compiler: gcc
sudo: false
cache: ccache