Coalesce write implementation in a single line down from three

Signed-off-by: Daniel Egger <daniel@eggers-club.de>

Author: therealprof

src/generate/register.rs

@@ -90,9 +90,7 @@ pub fn render(
             where
                 F: FnOnce(&mut W) -> &mut W
             {
-                let mut w = W::reset_value();
-                f(&mut w);
-                self.register.set(w.bits);
+                self.register.set(f(&mut W::reset_value()).bits);
             }
         });