rust/dcerpc: fix single_match clippy warning

warning: you seem to be trying to use `match` for destructuring a single pattern. Consider using `if let`
  --> src/dcerpc/log.rs:36:33
   |
36 |               DCERPC_TYPE_BIND => match &state.bind {
   |  _________________________________^
37 | |                 Some(bind) => {
38 | |                     jsb.open_array("interfaces")?;
39 | |                     for uuid in &bind.uuid_list {
...  |
51 | |                 None => {}
52 | |             },
   | |_____________^
   |
   = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#single_match
   = note: `#[warn(clippy::single_match)]` on by default

rust/src/dcerpc/log.rs

@@ -33,8 +33,7 @@ fn log_dcerpc_header_tcp(
                 jsb.set_uint("stub_data_size", tx.stub_data_buffer_ts.len() as u64)?;
                 jsb.close()?;
             }
-            DCERPC_TYPE_BIND => match &state.bind {
-                Some(bind) => {
+            DCERPC_TYPE_BIND => if let Some(bind) = &state.bind {
                 jsb.open_array("interfaces")?;
                 for uuid in &bind.uuid_list {
                     jsb.start_object()?;
@@ -47,8 +46,6 @@ fn log_dcerpc_header_tcp(
                     jsb.close()?;
                 }
                 jsb.close()?;
-                }
-                None => {}
             },
             _ => {}
         }