scylla_install_pkg is initially written for one-liner-installer, but now
it only used for creating AMI, and it just few lines of code, so it should be
merge into scylla_install_ami script.
Signed-off-by: Takuya ASADA <syuu@scylladb.com>
Message-Id: <20180612150106.26573-2-syuu@scylladb.com>
(cherry picked from commit 084c824d12)