Fake build opencl

We don't test it anyway, and the required packages is problematic
to install on travis currently

We cannot upgrade to 20.2 (because of dialyzer spec wrong for erl_tar:table/2)

.travis.yml

@@ -1,28 +1,34 @@
 language: erlang
 
 otp_release:
-  - 19.2
+  - 19.3
 
+dist: trusty
 sudo: false
 
 #notifications:
 #  email: false
 
-addons:
-  apt:
-    packages:
-    - git
-    - opencl-headers
-    - fglrx
+#addons:
+#  apt:
+#    packages:
+#    - fglrx
+#    - opencl-headers
 
 before_script:
   - set -e
   - git clone --depth 1 --branch cl-1.2.3 https://github.com/tonyrog/cl.git
   - export ERL_LIBS=`pwd`
   - export MAKEFLAGS=-j6
 
+#
+#  Fake a cl build since flgrx can not be installed in travis anymore, see
+#  https://github.com/travis-ci/travis-ci/issues/5221
+#  and thus cl can not be built but we need it below
+#
 script:
-  - (cd cl && rebar compile)
+  - (cd cl/src && erlc +debug_info -o../ebin *erl && cp cl.app.src ../ebin/cl.app)
+  - (mkdir cl/priv && touch cl/priv/cl.so )
   - make
 
 after_success: