SDK: add 'libelf-dev' package

Need `libelf-dev` package to be pre-installed for correct build of
VirtualBox guest additions.

Signed-off-by: Denis Pynkin <denis.pynkin@collabora.com>

apertis-ospack.yaml

@@ -501,6 +501,7 @@ actions:
       - libcogl-dev
       - libcogl-doc
       - libcurl4-nss-dev
+      - libelf-dev
       - libenchant-dev
       - libffi-dev
       - libgdata-doc