This clarifies that this is an LLVM specific variable and avoids
potential conflicts with other projects.
Differential Revision: https://reviews.llvm.org/D119918
This patch is a big sed to rename the following variables:
s/PYTHON_LIBRARIES/Python3_LIBRARIES/g
s/PYTHON_INCLUDE_DIRS/Python3_INCLUDE_DIRS/g
s/PYTHON_EXECUTABLE/Python3_EXECUTABLE/g
s/PYTHON_RPATH/Python3_RPATH/g
I've also renamed the CMake module to better express its purpose and for
consistency with FindLuaAndSwig.
Differential revision: https://reviews.llvm.org/D85976