install-dependencies: add rocky as a supported distro
install-dependencies: add rocky as a supported distro

this change should allow us to run install-dependencies.sh on
rockylinux which is a derivative of CentOS.

Signed-off-by: Kefu Chai <cdc92d111bae0ed1ee3b3c8a1f849fcffc6b44f7@gmail.com>
Message-Id: <20220510064435.1029618-1-cdc92d111bae0ed1ee3b3c8a1f849fcffc6b44f7@gmail.com>

avikivity/seastar,syuu1228/seastar,scylladb/seastar,scylladb/seastar,syuu1228/seastar,syuu1228/seastar,avikivity/seastar,avikivity/seastar,scylladb/seastar