Restore `cc` from mainline; clean up some cflags stuff.
Restore `cc` from mainline; clean up some cflags stuff.

iulian787/spack,krafczyk/spack,matthiasdiener/spack,mfherbst/spack,LLNL/spack,EmreAtes/spack,tmerrick1/spack,iulian787/spack,LLNL/spack,TheTimmy/spack,iulian787/spack,lgarren/spack,krafczyk/spack,mfherbst/spack,EmreAtes/spack,skosukhin/spack,matthiasdiener/spack,lgarren/spack,LLNL/spack,krafczyk/spack,matthiasdiener/spack,mfherbst/spack,lgarren/spack,skosukhin/spack,matthiasdiener/spack,mfherbst/spack,skosukhin/spack,tmerrick1/spack,TheTimmy/spack,lgarren/spack,krafczyk/spack,tmerrick1/spack,iulian787/spack,skosukhin/spack,krafczyk/spack,iulian787/spack,EmreAtes/spack,EmreAtes/spack,TheTimmy/spack,mfherbst/spack,TheTimmy/spack,EmreAtes/spack,TheTimmy/spack,LLNL/spack,matthiasdiener/spack,lgarren/spack,skosukhin/spack,tmerrick1/spack,tmerrick1/spack,LLNL/spack