Bind ignored results.

std::io::Error implements Drop in some configurations. A value that
implements Drop will be dropped immediately when not bound (and _ does
not bind). This is asymptomatic in this case but we want to deny this
behavior globally because it has very surprising behavior when the
"unused" value is a lock.

Bug: 281730184
Test: mm
Change-Id: I325f7bb1ca8eb74f56fbb3926e4e79e833a265a4
diff --git a/vmclient/src/lib.rs b/vmclient/src/lib.rs
index d67d87e..8f25b99 100644
--- a/vmclient/src/lib.rs
+++ b/vmclient/src/lib.rs
@@ -112,7 +112,7 @@
 
         // Wait for the child to signal that the RpcBinder server is ready
         // by closing its end of the pipe.
-        let _ = File::from(wait_fd).read(&mut [0]);
+        let _ignored = File::from(wait_fd).read(&mut [0]);
 
         Ok(VirtualizationService { client_fd })
     }