AArch64: migrate ADRP relaxation test to be llvm-mc only.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192281 91177308-0d34-0410-b5e6-96231b3b80d8
AArch64: enable MISched by default.

Substantial SelectionDAG scheduling is going away soon, and is
interfering with Hao's attempts to implement LDn/STn instructions, so
I say we make the leap first.

There were a few reorderings (inevitably) which broke some tests. I
tried to replace them with CHECK-DAG variants mostly, but some too
complex for that to be useful and I just reordered them.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192282 91177308-0d34-0410-b5e6-96231b3b80d8