Get rid of a use of extResType.
Get rid of a use of extResType.

ihc/futhark,CulpaBS/wbBach,mrakgr/futhark,HIPERFIT/futhark,diku-dk/futhark,mrakgr/futhark,ihc/futhark,HIPERFIT/futhark,HIPERFIT/futhark,diku-dk/futhark,diku-dk/futhark,ihc/futhark,diku-dk/futhark,diku-dk/futhark,mrakgr/futhark