This patch causes the installation of headers for the sanitizer and/or xray to...

This patch causes the installation of headers for the sanitizer and/or xray to be disabled when COMPILER_RT_BUILD_SANITIZERS=OFF and/or COMPILER_RT_BUILD_XRAY=OFF.

Reviewer: dberris

Subscribers: dberris, mgorny, llvm-commits, clm

Differential Revision: https://reviews.llvm.org/D31864

llvm-svn: 299940