Fix receiver type in Scheme{Sync,Async}::read

src/scheme.rs

@@ -239,7 +239,7 @@ pub trait SchemeAsync {
         Err(Error::new(EBADF))
     }
 
-    async fn read(&self, id: usize, buf: &mut [u8], offset: u64, fcntl_flags: u32, ctx: &CallerCtx) -> Result<usize> {
+    async fn read(&mut self, id: usize, buf: &mut [u8], offset: u64, fcntl_flags: u32, ctx: &CallerCtx) -> Result<usize> {
         Err(Error::new(EBADF))
     }
 
@@ -326,12 +326,10 @@ pub trait SchemeSync {
         Err(Error::new(EBADF))
     }
 
-
-    fn read(&self, id: usize, buf: &mut [u8], offset: u64, fcntl_flags: u32, ctx: &CallerCtx) -> Result<usize> {
+    fn read(&mut self, id: usize, buf: &mut [u8], offset: u64, fcntl_flags: u32, ctx: &CallerCtx) -> Result<usize> {
         Err(Error::new(EBADF))
     }
 
-
     fn write(&mut self, id: usize, buf: &[u8], offset: u64, fcntl_flags: u32, ctx: &CallerCtx) -> Result<usize> {
         Err(Error::new(EBADF))
     }