CMAKE_BUILD_WITH_INSTALL_RPATH

Use the install path for the RPATH.

Normally CMake uses the build tree for the RPATH when building executables etc on systems that use RPATH. When the software is installed the executables etc are relinked by CMake to have the install RPATH. If this variable is set to true then the software is always built with the install path for the RPATH and does not need to be relinked when installed.