rocm_install_targets does not honor cmake install locations

[trixirt]

In many linux distros, ROCm is not installed to /opt/rocm, but is packaged as a regular disto package. So the install location should work using normal normal cmake install variables. At https://github.com/ROCm/rocm-cmake/blob/develop/share/rocmcmakebuildtools/cmake/ROCMInstallTargets.cmake#L134 This works for windows, but not linux.

The problem shows up when build amdmigraphx and the install is to /usr/lib/migraphx/lib,include and not the expected /usr/lib,include