Fix empty backtraces when panicking

OSDK.toml

@@ -91,4 +91,4 @@ args = [
     "-device virtio-net-device,netdev=net01",
     "-device virtio-serial-device",
     "-device virtconsole,chardev=mux",
-]
+]

osdk/src/commands/build/mod.rs

@@ -133,6 +133,9 @@ fn build_kernel_elf(
         "-C code-model=kernel",
         "-C relocation-model=static",
         "-Z relro-level=off",
+        // We do not really allow unwinding except for kernel testing. However, we need to specify
+        // this to show backtraces when panicking.
+        "-C panic=unwind",
     ]);
 
     let mut command = cargo();

osdk/src/commands/test.rs

@@ -66,7 +66,7 @@ pub static KTEST_CRATE_WHITELIST: Option<&[&str]> = Some(&{:#?});
         &osdk_target_directory,
         &ws_target_directory,
         &required_build_config,
-        &["--cfg ktest", "-C panic=unwind"],
+        &["--cfg ktest"],
     );
     std::env::remove_var("RUSTFLAGS");
     std::env::set_current_dir(original_dir).unwrap();