rootdev: include missing header file.

This adds <sys/sysmacros.h> because the
inclusion of <sys/sysmacros.h> by <sys/types.h> is deprecated since
glibc 2.25.

BUG=chromium:865304
TEST=emerge-samus rootdev with glibc 2.27

Change-Id: Ic54e089659d620a862720b9882235117eb8487b5
Reviewed-on: https://chromium-review.googlesource.com/1143004
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Tested-by: Yunlian Jiang <yunlian@chromium.org>
Reviewed-by: Manoj Gupta <manojgupta@chromium.org>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
2 files changed
tree: 96689f9644457b68573b2c85022436b895f5b650
  1. LICENSE
  2. Makefile
  3. README.chromium
  4. main.c
  5. rootdev.c
  6. rootdev.h
  7. rootdev_test.sh