Ubuntu: unify libjpeg-turbo8 dependency

[Kikobeats]

Since libjpeg-turbo8-dev depends on libjpeg-turbo8, you don't need to explicitly install it:

apt-get install -y libjpeg-turbo8-dev
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following additional packages will be installed:
  libc-dev-bin libc6-dev libcrypt-dev libjpeg-turbo8 linux-libc-dev manpages manpages-dev

Also, remove duplicate dependencies to reduce the complexity 🙂

[dooman87]

Thanks!