add special case for power of 0.5 (#87912)
Workaround for https://github.com/pytorch/torchdynamo/issues/1775, and calling sqrt is better in any case, but `libdevice.pow` still for some reason doesn't work if both arguments are scalars
cc @jansel @mlazos @soumith @voznesenskym @yanboliang @penguinwu @anijain2305 @EikanWang @jgong5 @Guobing-Chen @chunyuan-w @XiaobingSuper @zhuhaozhe @blzheng @Xia-Weiwen @wenzhe-nrv @jiayisunx @mreso, can you please check if that takes you further with diffusers
cc @jansel @mlazos @soumith @voznesenskym @yanboliang @penguinwu @anijain2305 @EikanWang @jgong5 @Guobing-Chen @chunyuan-w @XiaobingSuper @zhuhaozhe @blzheng @Xia-Weiwen @wenzhe-nrv @jiayisunx
Pull Request resolved: https://github.com/pytorch/pytorch/pull/87912
Approved by: https://github.com/desertfire
