Rollup merge of #65016 - lzutao:inline-mem-constfn, r=oli-obk
Rollup merge of #65016 - lzutao:inline-mem-constfn, r=oli-obk

Always inline `mem::{size_of,align_of}` in debug builds

Those two are const fn and do not have any arguments. Inlining
helps reducing generated code size in debug builds.

See also #64996.

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