Revert r208417 (olista01 'ARM: HFAs must be passed in consecutive registers'). This is a followon commit from r208413 which broke the LLVM bots.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@208422 91177308-0d34-0410-b5e6-96231b3b80d8