qa: only run cocci tests on one linux builder

.travis.yml

@@ -16,9 +16,10 @@ script:
   - make
   - make check
 before_install:
-  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then sudo add-apt-repository -y ppa:npalix/coccinelle; fi
+  - if [[ "$TRAVIS_OS_NAME" == "linux" && "$CC" == "gcc" ]]; then sudo add-apt-repository -y ppa:npalix/coccinelle; fi
   - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then sudo apt-get update -qq; fi
-  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then sudo apt-get install -y libpcre3 libpcre3-dbg libpcre3-dev build-essential autoconf automake libtool libpcap-dev libnet1-dev libyaml-0-2 libyaml-dev zlib1g zlib1g-dev libcap-ng-dev libcap-ng0 make libmagic-dev libnetfilter-queue-dev libnetfilter-queue1 libnfnetlink-dev libnfnetlink0 coccinelle libjansson-dev libhiredis-dev; fi
+  - if [[ "$TRAVIS_OS_NAME" == "linux" && "$CC" == "gcc" ]]; then sudo apt-get install -y libpcre3 libpcre3-dbg libpcre3-dev build-essential autoconf automake libtool libpcap-dev libnet1-dev libyaml-0-2 libyaml-dev zlib1g zlib1g-dev libcap-ng-dev libcap-ng0 make libmagic-dev libnetfilter-queue-dev libnetfilter-queue1 libnfnetlink-dev libnfnetlink0 coccinelle libjansson-dev libhiredis-dev; fi
+  - if [[ "$TRAVIS_OS_NAME" == "linux" && "$CC" == "clang" ]]; then sudo apt-get install -y libpcre3 libpcre3-dbg libpcre3-dev build-essential autoconf automake libtool libpcap-dev libnet1-dev libyaml-0-2 libyaml-dev zlib1g zlib1g-dev libcap-ng-dev libcap-ng0 make libmagic-dev libnetfilter-queue-dev libnetfilter-queue1 libnfnetlink-dev libnfnetlink0 libjansson-dev libhiredis-dev; fi
   - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then brew update; fi
   - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then brew install pkg-config libmagic libyaml nss nspr jansson libnet lua pcre hiredis; fi
   - ./qa/travis-libhtp.sh