ARM MC: Fix the initial DWARF CFI unwind info at the start of a function

This brings MC into line with GNU 'as' on ARM, and it brings the ARM
target into line with most other LLVM targets, which declare the
initial CFI state with addInitialFrameState().

Without this, functions generated with .cfi_startproc/endproc on ARM
will tend to cause GDB to abort with:
  gdb/dwarf2-frame.c:1132: internal-error: Unknown CFA rule.

I've also tested this by comparing the output of "readelf -w" on the
object files produced by llvm-mc and gas when given the .s file added
here.

This change is part of addressing PR18636.

Differential Revision: http://llvm-reviews.chandlerc.com/D2597

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200255 91177308-0d34-0410-b5e6-96231b3b80d8
Fix the "#ifndef HAVE_SYS_WAIT_H" code path in Program.inc to compile

Without this fix, WaitResult is not defined.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@200259 91177308-0d34-0410-b5e6-96231b3b80d8