[cmake] add initial travis checks (#4112)

.travis/before_install.sh

@@ -42,6 +42,11 @@ cd /tmp || die
     (cd /etc/apt/sources.list.d && sudo rm -rf cassandra.list* couchdb.list* mongodb-3.4.list* rabbitmq_rabbitmq-server.list* chris-lea-redis-server.list* github_git-lfs.list* pgdg.list)
     sudo apt-get update || die
 
+    sudo apt-get install ninja-build
+
+    pip3 install --upgrade pip
+    pip3 install cmake
+
     [ $BUILD_TARGET != posix-distcheck -a $BUILD_TARGET != posix-32-bit -a $BUILD_TARGET != posix-app-cli -a $BUILD_TARGET != posix-mtd -a $BUILD_TARGET != posix-ncp -a $BUILD_TARGET != posix-app-ncp ] || {
         pip install --upgrade pip || die
         pip install -r $TRAVIS_BUILD_DIR/tests/scripts/thread-cert/requirements.txt || die

.travis/script.sh

@@ -118,6 +118,13 @@ build_cc1352() {
 }
 
 build_cc2538() {
+    git checkout -- . || die
+    git clean -xfd || die
+    mkdir build && cd build || die
+    cmake -GNinja -DCMAKE_TOOLCHAIN_FILE=examples/platforms/cc2538/arm-none-eabi.cmake -DOT_PLATFORM=cc2538 .. || die
+    ninja || die
+    cd .. || die
+
     git checkout -- . || die
     git clean -xfd || die
     ./bootstrap || die
@@ -409,6 +416,13 @@ build_samr21() {
 }
 
 [ $BUILD_TARGET != posix ] || {
+    git checkout -- . || die
+    git clean -xfd || die
+    mkdir build && cd build || die
+    cmake -GNinja -DOT_PLATFORM=posix .. || die
+    ninja || die
+    cd .. || die
+
     git checkout -- . || die
     git clean -xfd || die
     ./bootstrap || die