[Dependencies][iOS]Hacked SDL build script as newest toolchain doesn't like armv6. I don't want to spend time on finding why armv6 can 't be compiled, as we will not support it anyway.

Could probably fill an issue to SDL devs, or pull latest changes from SDL repo.
[mac]Maintain consistency with configure prefix for SDL build. In iOS will be <SDLDir>/build/iOS/lib. For mac will then be <SDLDir>/build/iOS/lib