block: Implement SparseCapable trait for RawFileDiskSync

Add disk_file::SparseCapable trait implementation for
RawFileDiskSync. Delegates to probe_sparse_support() to
detect whether the underlying file supports hole-punching.

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

block/src/raw_sync.rs

@@ -96,6 +96,12 @@ impl disk_file::Geometry for RawFileDiskSync {
     }
 }
 
+impl disk_file::SparseCapable for RawFileDiskSync {
+    fn supports_sparse_operations(&self) -> bool {
+        probe_sparse_support(&self.file)
+    }
+}
+
 pub struct RawFileSync {
     fd: RawFd,
     eventfd: EventFd,