ash runner: cleanup debug callback

Author: Firestar99

examples/runners/ash/src/device.rs

@@ -170,16 +170,8 @@ unsafe extern "system" fn vulkan_debug_callback(
     _user_data: *mut std::os::raw::c_void,
 ) -> vk::Bool32 {
     let callback_data = unsafe { *p_callback_data };
-    let message_id_name = if callback_data.p_message_id_name.is_null() {
-        Cow::from("")
-    } else {
-        unsafe { CStr::from_ptr(callback_data.p_message_id_name).to_string_lossy() }
-    };
-    let message = if callback_data.p_message.is_null() {
-        Cow::from("")
-    } else {
-        unsafe { CStr::from_ptr(callback_data.p_message).to_string_lossy() }
-    };
+    let message_id_name = callback_data.message_id_name_as_c_str().unwrap_or(c"");
+    let message = callback_data.message_as_c_str().unwrap_or(c"");
     println!("{message_severity:?}: [{message_id_name}] : {message}");
     vk::FALSE
 }