Fix for newer nightly

src/lib.rs

 #![crate_name = "orbclient"]
 #![crate_type = "lib"]
-#![cfg_attr(feature = "no_std", feature(alloc))]
 #![cfg_attr(feature = "no_std", no_std)]
-#![deny(warnings)]
 
 #[cfg(feature = "no_std")]
 extern crate alloc;

src/renderer.rs

@@ -515,7 +515,7 @@ pub trait Renderer {
             let start = offset + l * width;
             let mut stop = start + w;
             let begin = l * w;
-            let mut end = begin + w;
+            let end = begin + w;
 
             //check boundaries
             if start_x + w > width {