Revert r213467, it breaks non-thumb mode.


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@213479 91177308-0d34-0410-b5e6-96231b3b80d8
Redo THUMB support.

Discussed with and tested by: Saleem Abdulrasool


git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@213481 91177308-0d34-0410-b5e6-96231b3b80d8