Miri: mplace_access_checked: offer option to force different alignment on place
Miri: mplace_access_checked: offer option to force different alignment on place

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