Sink DI metadata usage out of MachineInstr.h and MachineInstrBuilder.h

MachineInstr.h and MachineInstrBuilder.h are very popular headers,
widely included across all LLVM backends. It turns out that there only a
handful of TUs that actually care about DI operands on MachineInstrs.

After this change, touching DebugInfoMetadata.h and rebuilding llc only
needs 112 actions instead of 542.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@266351 91177308-0d34-0410-b5e6-96231b3b80d8
11 files changed