Unwinding for ARM option2

Partial Fix for #5265

- Enabling LLVM ARM ehabi option.
- Add ARM debug information manually for ccall.s
- Compile object file using Android-NDK.

Current LLVM trunk version can generate ARM debug information for assembly files but it is incomplete for object files. Unwinding on ARM can be done with LLVM trunk(the LLVM submodule of rust has problem on generating ARM debug information). See #5368

The Android-NDK detour(0f89eab) can be removed after LLVM has complete feature of generating ARM debug information for object file.