Rollup merge of #56751 - mbrubeck:hash, r=dtolnay
Rollup merge of #56751 - mbrubeck:hash, r=dtolnay

Allow ptr::hash to accept fat pointers

Fat pointers implement Hash since #45483.  This is a follow-up to #56250.

GBGamer/rust,graydon/rust,graydon/rust,GBGamer/rust,GBGamer/rust,GBGamer/rust,GBGamer/rust,graydon/rust,aidancully/rust,GBGamer/rust,graydon/rust,aidancully/rust,aidancully/rust,GBGamer/rust,aidancully/rust,aidancully/rust,graydon/rust,aidancully/rust,graydon/rust,GBGamer/rust