[ARM] Add use-misched feature, to enable the MachineScheduler.
Summary:
This change makes it easier to experiment with the MachineScheduler in
the ARM backend and also makes it very explicit which CPUs use the
MachineScheduler (currently only swift and cyclone).
Reviewers: MatzeB, t.p.northover, javed.absar
Reviewed By: MatzeB
Subscribers: aemerson, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D35935
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@309316
91177308-0d34-0410-b5e6-
96231b3b80d8