cheets-libffi: Fix compilation of 32-bit library on x86/x86_64

32-bit libffi requires different source files than 64-bit ones.
Moreover, regardless of target system, win32.S is always needed. Also
additional define is required to select code path supported by GNU
Assembler version provided by Android x86/x86_64 toolchain.

Change-Id: I0d2e17a8ee08fd28d0f8b7649b9e444932819874
1 file changed