Rollup merge of #61557 - alexcrichton:build-less, r=pietroalbini

Rollup merge of #61557 - alexcrichton:build-less, r=pietroalbini

rustbuild: Include `rustfmt` in deduplicated dependencies

Currently `rustfmt` is excluded from the "don't build dependencies
twice" check but it's currently building dependencies twice! Namely big
dependencies like `rustc-ap-syntax` are built once for rustfmt and once
for the RLS. This commit includes `rustfmt` in these checks and then
fixes the resulting feature mismatches for winapi.