he he as I explained on the Rust Web development hosting topic, I tried to do exactly the same 
The easiest way is to use the arm-unknown-linux-gnueabihf instead. I guess the best way would be to have the std library for armv7 compiled without NEON, and compile your code without NEON. In theory you can disable NEON extension by setting RUSTFLAGS="-C target-feature=-neon" to cargo, but I don't know if this works.