devel/sd-mux-ctrl: Rename to match upstream

Rename devel/sd-mux to devel/sd-mux-ctrl and remove dupplicate port
sysutils/sd-mux-ctrl added recently. As the port names were different
addport -y didn't catch the duplicate when looking at the catalog tree
INDEX. Also add entries into MOVED.

Approved by: swills
Differential Revision: https://reviews.freebsd.org/D29732