rust: samples: use try_format! in sample module

Signed-off-by: Mateusz Jabłoński <[email protected]>

Author: jablonskim

samples/rust/rust_minimal.rs

@@ -5,6 +5,7 @@
 #![no_std]
 #![feature(allocator_api, global_asm)]
 
+use alloc::try_format;
 use kernel::prelude::*;
 
 module! {
@@ -25,7 +26,7 @@ impl KernelModule for RustMinimal {
         pr_info!("Am I built-in? {}\n", !cfg!(MODULE));
 
         Ok(RustMinimal {
-            message: "on the heap!".try_to_owned()?,
+            message: try_format!("on the {}!", "heap")?,
         })
     }
 }