Resolve "Add saturn cores"

Please make sure your MR is ready to be merged !

• You added the changes in CHANGELOG.md
• You described the MR as below
• You updated the recalbox wiki
• You wrote a blog post on recalbox-blog

Changes :

• Adds saturn cores on pc, but kronos
• Yabasanshiro compiles on xu4 but it has sound issues (laggy), so don't activate it yet
• Info: https://github.com/libretro/yabause/issues/116
• Check if kronos needs bios/kronos or just bios suffice

Related to :

• link other PR or issues here

Closes #939 (closed)