Make CoinMP build for Android

(No idea whether it works, of course.)

Patch the config.sub files to recognize arm-linux-androideabi.

Don't build any binary programs as that fails for Android becuase we don't
pass in the right C++ library to use anyway. (And those programs aren't really
useful to us anyway, on any platform, I guess?)

Change-Id: I70c7a527db41081a51548ce6983b6a9ae8a08bc7