[ios] - backports from linusyang

This are some nice commits from linusyang' ios64 bit branch. Those are the changes:

1. use lzma for deb package - reduces the size from 56mb to 36mb for ios and atv2
2. provide gen_entitlements which was hardcoded to /Developer/blahblah for now and always needed extra steps for clean build systems
3. add fakeroot to native buildtools and use this during deb creation - this is the alternative to libfauxsu
4. fixes the linker warning about addreses > 4gb
5. Should add the current ios icon to cydia

For review please @davilla and @amet (for the deb changes)

thx to @linusyang