block: Implement Resizable trait for RawFileDiskSync

Add disk_file::Resizable trait implementation for
RawFileDiskSync. Calls file.set_len(size) and wraps the
I/O error in BlockError on failure.

Signed-off-by: Muminul Islam <muislam@microsoft.com>

block/src/raw_sync.rs

@@ -102,6 +102,14 @@ impl disk_file::SparseCapable for RawFileDiskSync {
     }
 }
 
+impl disk_file::Resizable for RawFileDiskSync {
+    fn resize(&mut self, size: u64) -> BlockResult<()> {
+        self.file
+            .set_len(size)
+            .map_err(|e| BlockError::new(BlockErrorKind::Io, DiskFileError::ResizeError(e)))
+    }
+}
+
 pub struct RawFileSync {
     fd: RawFd,
     eventfd: EventFd,