Introduce a delay after each step of initialization

Introduce a short delay after each step of the initialization sequence.
This is a try to fix a problem with failing device initialization,
seen on some KVM switches.

References #161

eruption/src/hwdevices/roccat_vulcan_1xx.rs

@@ -23,6 +23,8 @@ use log::*;
 use parking_lot::{Mutex, RwLock};
 use std::collections::HashMap;
 use std::sync::Arc;
+use std::thread;
+use std::time::Duration;
 use std::{any::Any, mem::size_of};
 
 use crate::constants;
@@ -464,6 +466,8 @@ impl RoccatVulcan1xx {
 
                     Err(_) => return Err(HwDeviceError::InvalidResult {}.into()),
                 }
+
+                thread::sleep(Duration::from_millis(70));
             }
         }
     }