This has been removed a long time ago. Please use only -Dpython=ON when configuring, although that is already the default (in current master that is now called -Dpyroot=ON though). Also, you might have better luck with -DCMAKE_PREFIX_PATH=$HOME/python-3.5.7 instead of setting other variables. It’s also recommended to only set PYTHON_EXECUTABLE and leave the library and include paths for CMake to figure out. Another thing is that you are trying to use a static library for python and that likely won’t work with ROOT. You need to recompile your Python with --enable-shared or similar to use it with ROOT. You should make sure to use the same GCC for ROOT and your custom Python as well, just in case.
BTW, if you have no network, you should add -Dimt=OFF, otherwise ROOT will try to download TBB by default. Same for the xrootd option (which may require network to download the bultin xrootd).