feat: use rustembedded/cross images and use static relocation model to fix cross-compile

DEPLOY.md

@@ -37,7 +37,7 @@ $ cargo build --release
 
 Note that this currently requires Rust 1.50.
 
-If you want to cross compile Conduit to another architecture, read the [Cross-Compile Guide](CROSS_COMPILE.md).
+If you want to cross compile Conduit to another architecture, read the [Cross-Compile Guide](cross/README.md).
 
 ## Adding a Conduit user