Split build commands as suggested by @Youw

Author: FloopCZ

tensorflow_cc/cmake/TensorflowShared.cmake

@@ -16,17 +16,15 @@ ExternalProject_Add(
         COMMAND cp "${CMAKE_CURRENT_SOURCE_DIR}/patches/v1.15.0-workspace.bzl.patch" .
         COMMAND git apply v1.15.0-workspace.bzl.patch
   CONFIGURE_COMMAND tensorflow/contrib/makefile/compile_linux_protobuf.sh
-            # Do not fail on warnings when building nsync
-            COMMAND sed -i "s/ -Werror//g" tensorflow/contrib/makefile/compile_nsync.sh
-            COMMAND tensorflow/contrib/makefile/compile_nsync.sh
-            COMMAND "${CMAKE_CURRENT_BINARY_DIR}/build_tensorflow.sh"
-            COMMAND "${CMAKE_CURRENT_SOURCE_DIR}/cmake/copy_links.sh" .
-            # For some reason, Bazel sometimes puts the headers into
-            # `bazel-genfiles/genfiles` and sometimes just to `bazel-genfiles`.
-            # So we just create and include both the directories.
-            COMMAND mkdir -p bazel-genfiles/genfiles
-            COMMAND touch bazel-genfiles/_placeholder.h
-            COMMAND touch bazel-genfiles/genfiles/_placeholder.h
-  BUILD_COMMAND ""
-  INSTALL_COMMAND ""
+           # Do not fail on warnings when building nsync
+           COMMAND sed -i "s/ -Werror//g" tensorflow/contrib/makefile/compile_nsync.sh
+           COMMAND tensorflow/contrib/makefile/compile_nsync.sh
+  BUILD_COMMAND "${CMAKE_CURRENT_BINARY_DIR}/build_tensorflow.sh"
+  INSTALL_COMMAND "${CMAKE_CURRENT_SOURCE_DIR}/cmake/copy_links.sh" .
+         # For some reason, Bazel sometimes puts the headers into
+         # `bazel-genfiles/genfiles` and sometimes just to `bazel-genfiles`.
+         # So we just create and include both the directories.
+         COMMAND mkdir -p bazel-genfiles/genfiles
+         COMMAND touch bazel-genfiles/_placeholder.h
+         COMMAND touch bazel-genfiles/genfiles/_placeholder.h
 )