Auto merge of #111836 - calebzulawski:target-feature-closure, r=workingjubilee

Fix #[inline(always)] on closures with target feature 1.1

Fixes #108655.  I think this is the most obvious solution that isn't overly complicated.  The comment includes more justification, but I think this is likely better than demoting the `#[inline(always)]` to `#[inline]`, since existing code is unaffected.

Author: bors