Auto merge of #143334 - Stypox:layout_of-inline, r=<try>

Always inline InterpCx::layout_of after perf regression

Followup to #142721 to fix the performance regression. I ran one quick benchmark locally (`ctfe-stress-5`) and it does seem to be faster. I further tried adding `#[inline(always)]` to `compiler/rustc_middle/src/ty/layout.rs` in `layout_of()` under `LayoutOfHelpers` but that didn't change the benchmark results at all.

`@rust-timer` build e7e3c9e

(I'm not sure I have permission to do the above)

r? `@RalfJung`

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Author: rust-bors[bot]

compiler/rustc_const_eval/src/interpret/eval_context.rs

@@ -96,7 +96,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
     /// This inherent method takes priority over the trait method with the same name in LayoutOf,
     /// and allows wrapping the actual [LayoutOf::layout_of] with a tracing span.
     /// See [LayoutOf::layout_of] for the original documentation.
-    #[inline]
+    #[inline(always)]
     pub fn layout_of(
         &self,
         ty: Ty<'tcx>,