WIP: Resolve "Add mupen64plus-nx on xu4 and pc"

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 :

• describe changes here

Related to :

• link other PR or issues here

Closes #1201 (closed)