add elfutils to host packages.

This adds elfutils to host packages. The reason to add this package
is the the strip from binutils has a bug and it makes the coredump
cannot be symbolized. See b:65296759. To workaround that, we want to
use eu-strip from elfutils.

BUG=chromium:701659
TEST=cbuildbot chromiumos-sdk

Change-Id: If8bee73c5ddea9bc7a5e0abc39df12311e534b7e
Reviewed-on: https://chromium-review.googlesource.com/1028845
Commit-Ready: Yunlian Jiang <yunlian@chromium.org>
Tested-by: Yunlian Jiang <yunlian@chromium.org>
Reviewed-by: Manoj Gupta <manojgupta@chromium.org>
Reviewed-by: Caroline Tice <cmtice@chromium.org>
diff --git a/scripts/cros_setup_toolchains.py b/scripts/cros_setup_toolchains.py
index 80836df..99344d6 100644
--- a/scripts/cros_setup_toolchains.py
+++ b/scripts/cros_setup_toolchains.py
@@ -134,6 +134,7 @@
       'llvm': 'sys-devel',
       'libcxxabi': 'sys-libs',
       'libcxx': 'sys-libs',
+      'elfutils': 'dev-libs',
   }
 
   @classmethod