Auto merge of #117029 - rmehri01:mir_opt_filecheck_inline_tests, r=cjgillot

Add FileCheck annotations to MIR-opt inlining tests

Part of #116971, adds FileCheck annotations to MIR-opt tests in `tests/mir-opt/inline`.

I left out a few (such as `inline_cycle`) where it mentioned that the particular outcome of inlining isn't important, just that the inliner doesn't get stuck in an infinite loop.

r? cjgillot

Author: bors