Fix validation on substituted callee bodies in MIR inliner

[compiler-errors]

When inlining a coroutine, we will substitute the MIR body with the args of the call. There is code in the MIR validator that attempts to prevent query cycles, and will use the coroutine body directly when it detects that's the body that's being validated. That means that when inlining a coroutine body that has been substituted, it may no longer be parameterized over the original args of the coroutine, which will lead to substitution ICEs.

Fixes #119064

[rustbot]

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[rustbot]

Some changes occurred to MIR optimizations

cc @rust-lang/wg-mir-opt

[Nadrieril]

r? compiler

[compiler-errors]

@rustbot ready

[cjgillot]

r=me after rebase

[compiler-errors]

@bors r=cjgillot

[bors]

:pushpin: Commit 78ebb939c1f7135bcc851ba9d4d091d40bb7fe64 has been approved by cjgillot

It is now in the queue for this repository.