edition: Fill in macro imports

Macros were previously imported through `#[macro_use] extern crate`,
which is basically a glob import of all macros from the crate. As of
2018 edition of Rust, `extern crate` is no longer required and macros
are imported individually like any other item from a dependency. This CL
fills in all the appropriate macro imports that will allow us to remove
our use of `extern crate` in a subsequent CL.

TEST=cargo check --all-features --tests
TEST=kokoro

Change-Id: If2ec08b06b743abf5f62677c6a9927c3d5d90a54
Reviewed-on: https://chromium-review.googlesource.com/1565546
Commit-Ready: David Tolnay <dtolnay@chromium.org>
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Tested-by: David Tolnay <dtolnay@chromium.org>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: David Tolnay <dtolnay@chromium.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/qcow/src/qcow.rs b/qcow/src/qcow.rs
index 8178212..9015bb1 100644
--- a/qcow/src/qcow.rs
+++ b/qcow/src/qcow.rs
@@ -15,7 +15,7 @@ mod vec_cache;
 use byteorder::{BigEndian, ReadBytesExt, WriteBytesExt};
 use libc::{EINVAL, ENOSPC, ENOTSUP};
 use remain::sorted;
-use sys_util::{FileSetLen, FileSync, PunchHole, SeekHole, WriteZeroes};
+use sys_util::{error, FileSetLen, FileSync, PunchHole, SeekHole, WriteZeroes};
 
 use std::cmp::min;
 use std::fmt::{self, Display};