wasmer-cli: refuse to build if not at least one compiler is enabled

lib/cli/src/bin/wasmer.rs

@@ -1,5 +1,10 @@
 use wasmer_cli::cli::wasmer_main;
 
+#[cfg(not(any(feature = "cranelift", feature = "singlepass", feature = "llvm")))]
+compile_error!(
+    "Either enable at least one compiler, or compile the wasmer-headless binary instead"
+);
+
 fn main() {
     wasmer_main();
 }