Rollup merge of #52905 - pravic:unsize-typo, r=alexcrichton
Rollup merge of #52905 - pravic:unsize-typo, r=alexcrichton

Fix a typo in unsize.rs

RfC -> RFC

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