CI: travis-ci: switch BoringSSL builds to ninja

using ninja instead of make speed up build by 40 sec

.travis.yml

@@ -21,7 +21,7 @@ env:
 addons:
   apt:
     update: true
-    packages: [ liblua5.3-dev, libsystemd-dev, libpcre2-dev, clang-9, socat ]
+    packages: [ liblua5.3-dev, libsystemd-dev, libpcre2-dev, clang-9, socat, ninja-build ]
   homebrew:
     update: true
     packages: [ socat ]

scripts/build-ssl.sh

@@ -100,8 +100,8 @@ if [ ! -z ${BORINGSSL+x} ]; then
         if [ -d build ]; then rm -rf build; fi
 	mkdir build
 	cd build
-	cmake -DCMAKE_BUILD_TYPE=release -DBUILD_SHARED_LIBS=1 ..
-	make
+	cmake  -GNinja -DCMAKE_BUILD_TYPE=release -DBUILD_SHARED_LIBS=1 ..
+	ninja
 
 	rm -rf ${SSL_LIB} || exit 0
 	rm -rf ${SSL_INC} || exit 0