Improve SOAC handling in hoister.
Improve SOAC handling in hoister.

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