Fix rpm build warning/error: absolute symlink
    
    I noticed that warnings and errors show up in the `RPM build errors:`
    output. When I produced an error I did see this warning about absolute
    symlink showing up:
    
    ```
    absolute symlink: /usr/lib64/bfd-plugins/LLVMgold.so -> /usr/lib64/LLVMgold.so
    ```
    
    The upstream RPM fix to log warnings and errors separately is here:
    
    https://github.com/rpm-software-management/rpm/pull/1590
    
    Thanks to @sergesanspaille for the help.