cmake: fix Python executable with cmake

Currently, CMake has two ways of finding Python executables:
FindPythonInterp and FindPython/FindPython3. FindPythonInterp is
deprecated and may be removed at some point. Currently, python3native
sets PYTHON_EXECUTABLE, which FindPythonInterp uses. This is a problem
for a few reasons:

- Setting PYTHON_EXECUTABLE as an environment variable doesn't work, as
  CMake needs it to be set as an explicit CMake option via -D.
- Projects using the newer FindPython/FindPython3 don't pickup the right
  Python, as the newer routines use Python_EXECUTABLE and
  Python3_EXECUTABLE.

Fix this by setting PYTHON_EXECUTABLE, Python_EXECUTABLE, and
Python3_EXECUTABLE using -D options to EXTRA_OECMAKE.

The CMake routines are documented below:
https://cmake.org/cmake/help/latest/module/FindPythonInterp.html
https://cmake.org/cmake/help/latest/module/FindPython.html
https://cmake.org/cmake/help/latest/module/FindPython3.html

Signed-off-by: Martin Kelly <mkelly@xevo.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

0 files changed, 0 insertions, 0 deletions