intel/compiler: Don't store stage name and abbrev

intel/compiler: Don't store stage name and abbrev

Those are used in the failure paths and are easily retriavable from the
stage itself, so no need to store them.

Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Sagar Ghuge <sagar.ghuge@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25367>