CI: travis: revert to clang-7 for BoringSSL tests

Building BoringSSL with clang9 fails:
   https://travis-ci.com/github/haproxy/haproxy/jobs/298267505
   https://bugs.chromium.org/p/boringssl/issues/detail?id=323

Let's revert to clang-7 for now.

diff --git a/.travis.yml b/.travis.yml
index 23b656a..5808386 100644 (file)
--- a/.travis.yml
+++ b/.travis.yml
@@ -81,7 +81,7 @@ matrix:
   - os: linux
     if: type == cron
     compiler: clang
-    env: TARGET=linux-glibc BORINGSSL=yes CC=clang-9
+    env: TARGET=linux-glibc BORINGSSL=yes
   - os: linux
     if: type != cron
     compiler: clang