Fix new/improved Rust 1.63 clippy lints (#649)

More `clippy::use_self` is found in manual code, and superfluous
transmutes in bindgen output are now also found and disallowed.

Author: MarijnS95

ash/src/entry.rs

@@ -377,17 +377,17 @@ mod loaded {
     impl fmt::Display for LoadingError {
         fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
             match self {
-                LoadingError::LibraryLoadFailure(err) => fmt::Display::fmt(err, f),
-                LoadingError::MissingEntryPoint(err) => fmt::Display::fmt(err, f),
+                Self::LibraryLoadFailure(err) => fmt::Display::fmt(err, f),
+                Self::MissingEntryPoint(err) => fmt::Display::fmt(err, f),
             }
         }
     }
 
     impl Error for LoadingError {
         fn source(&self) -> Option<&(dyn Error + 'static)> {
             Some(match self {
-                LoadingError::LibraryLoadFailure(err) => err,
-                LoadingError::MissingEntryPoint(err) => err,
+                Self::LibraryLoadFailure(err) => err,
+                Self::MissingEntryPoint(err) => err,
             })
         }
     }

ash/src/vk.rs

@@ -27,7 +27,7 @@ pub use features::*;
 mod prelude;
 pub use prelude::*;
 /// Native bindings from Vulkan headers, generated by bindgen
-#[allow(nonstandard_style)]
+#[allow(clippy::useless_transmute, nonstandard_style)]
 pub mod native;
 mod platform_types;
 pub use platform_types::*;