Rollup merge of #36765 - frewsxcv:ptr-write-bytes, r=steveklabnik
Rollup merge of #36765 - frewsxcv:ptr-write-bytes, r=steveklabnik

Add basic doc example for `core::ptr::write_bytes`.

None

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