misc: vmm: drop extern crate, use modern rust

This commit is part of a series of similar commits.

Signed-off-by: Philipp Schuster <philipp.schuster@cyberus-technology.de>
On-behalf-of: SAP philipp.schuster@sap.com

vmm/src/api/http/mod.rs

@@ -15,6 +15,7 @@ use std::sync::mpsc::Sender;
 use std::thread;
 
 use hypervisor::HypervisorType;
+use log::error;
 use micro_http::{
     Body, HttpServer, MediaType, Method, Request, Response, ServerError, StatusCode, Version,
 };