Revert "Inlining: Run the legacy AlwaysInliner before the regular inliner."

Revert "Inlining: Run the legacy AlwaysInliner before the regular inliner."

This seems to cause large regressions in existing code, as much as 75% slower
(4x the time taken). Small always inline functions seem to be used a lot in the
cmsis-dsp library.

I would add a phase ordering test to show the problems, but one already exists!
The llvm/test/Transforms/PhaseOrdering/ARM/arm_mult_q15.ll was just changed by
removing alwaysinline to hide the problems that existed.

This reverts commit cae033dcf227aeecf58fca5af6fc7fde1fd2fb4f.
This reverts commit 8e33c41e72ad42e4c27f8cbc3ad2e02b169637a1.