cmake: remove custom CMAKE_INSTALL_RPATH (#46685)

The CMake builder in Spack actually adds incorrect rpaths. They are
unfiltered and incorrectly ordered compared to what the compiler wrapper
adds.

There is no need to specify paths to dependencies in `CMAKE_INSTALL_RPATH`
because of two reasons:

1. CMake preserves "toolchain" rpaths, which includes the rpaths injected
   by our compiler wrapper.
2. We use `CMAKE_INSTALL_RPATH_USE_LINK_PATH=ON`, so libraries we link
   to are rpath'ed automatically.

However, CMake does not create install rpaths to directories in the package's
own install prefix, so we set `CMAKE_INSTALL_RPATH` to the educated guess
`<prefix>/{lib,lib64}`, but omit dependencies.

0 files changed, 0 insertions, 0 deletions