rust_binder: remove trailing comma

This prepares for a later commit in which we introduce a custom
formatting macro; that macro doesn't handle trailing commas so just
remove this one.

Reviewed-by: Alice Ryhl <[e-mail]>
Signed-off-by: Tamir Duberstein <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Miguel Ojeda <[e-mail]>

drivers/android/binder/process.rs

···
                     "  ref {}: desc {} {}node {debug_id} s {strong} w {weak}",
                     r.debug_id,
                     r.handle,
-                    if dead { "dead " } else { "" },
+                    if dead { "dead " } else { "" }
                 );
             }
         }