drirc: Allow extension midshader for Metro Redux
This fixes both Metro 2033 Redux and Metro Last Light Redux Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=99730 Signed-off-by:Eero Tamminen <eero.t.tamminen@intel.com> Signed-off-by:
Vadym Shovkoplias <vadym.shovkoplias@globallogic.com> Reviewed-by:
Tapani Pälli <tapani.palli@intel.com>