Commits
Uwe L. Korn authored and Wes McKinney committed 0831222cb1b
ARROW-4613: [C++] Set CMAKE_INSTALL_LIBDIR in gtest thirdparty build Author: Uwe L. Korn <uwelk@xhochy.com> Closes #3686 from xhochy/ARROW-4613 and squashes the following commits: 9237844de <Uwe L. Korn> ARROW-4613: Hardcode libdir in gtest thirdparty build