ARMGenEDInfo.inc unconditionally required

Hi,

I'm on Linux 32-bit, and I have configured LLVM to compile the X86
backend only. Now I can't compile LLVM at all, because
EDDisassembler.cpp tries to include the non-existing ARMGenEDInfo.inc.

I suspect that generation of this file depends on the ARM backend being
enabled, while including it doesn't. Am I right, or is there a different
cause?

Sebastian