JDK-8172670 removed the dependency on libelf but it's still referenced in a couple places, including autoconf files:

$ ack libelf make/
make/devkit/Tools.gmk
87: elfutils-libelf elfutils-libelf-devel \

$ ack libelf common/
common/autoconf/configure.ac
226:# Hotspot setup depends on lib checks (AOT needs libelf).

common/autoconf/generated-configure.sh
4217: PKGHANDLER_COMMAND="sudo apt-get install libelf-dev" ;;
4238: PKGHANDLER_COMMAND="sudo yum install elfutils-libelf-devel" ;;
65608:# Hotspot setup depends on lib checks (AOT needs libelf).

common/autoconf/help.m4
127: PKGHANDLER_COMMAND="sudo apt-get install libelf-dev" ;;
148: PKGHANDLER_COMMAND="sudo yum install elfutils-libelf-devel" ;;

common/doc/building.html
61:<li><a href="#libelf">libelf</a></li>
472:<h3 id="libelf">libelf</h3>
473:<p>libelf from the <a href="http://sourceware.org/elfutils">elfutils project</a> is required when building the AOT feature of Hotspot.</p>
475:<li>To install on an apt-based Linux, try running <code>sudo apt-get install libelf-dev</code>.</li>
476:<li>To install on an rpm-based Linux, try running <code>sudo yum install elfutils-libelf-devel</code>.</li>
478:<p>Use <code>--with-libelf=&lt;path&gt;</code> if <code>configure</code> does not properly locate your libelf files.</p>
540:<li><code>--with-libelf=&lt;path&gt;</code> - Set the path to <a href="#libelf">libelf</a></li>

common/doc/building.md
651:### libelf
653:libelf from the [elfutils project](http://sourceware.org/elfutils) is required
657: libelf-dev`.
659: elfutils-libelf-devel`.
661:Use `--with-libelf=<path>` if `configure` does not properly locate your libelf
816: * `--with-libelf=<path>` - Set the path to [libelf](#libelf)

common/nb_native/nbproject/configurations.xml
153: <in>salibelf.c</in>
32200: <item path="../../hotspot/src/jdk.hotspot.agent/linux/native/libsaproc/salibelf.c"
32206: <Elem>THIS_FILE="salibelf.c"</Elem>