Allow build environment to tweak cmake flags

bundle/bundle-linux.sh

@@ -226,6 +226,7 @@ ${GIT_C} submodule update --remote
 mkdir -p "${BUILD_DIRECTORY}"
 cd "${BUILD_DIRECTORY}"
 ${CMAKE} \
+    ${EXTRA_CMAKE_ARGS} \
     -C "${SOURCE_DIRECTORY}/build_files/cmake/config/blender_benchmark.cmake" \
     -D CMAKE_INSTALL_PREFIX="${BUNDLE_DIRECTORY}" \
     "${SOURCE_DIRECTORY}"