[SE] Let users specify CUDA path

Summary: Add logic to allow users to specify the CUDA path at configuration time.

Reviewers: jlebar

Subscribers: beanz, mgorny, jlebar, jprice, parallel_libs-commits

Differential Revision: https://reviews.llvm.org/D24580

llvm-svn: 281626
GitOrigin-RevId: b2d62bd071c6e005483c9fa5b917d7261295eb0c
4 files changed