[BUGFIX] Use MM_oppositeUsage for category relations

The MM_oppositeUsage property allows to apply match fields
of the opposite relation to MM records. This feature shall
be enabled for sys_category records as well.

Resolves: #56122
Related: #56061
Releases: 6.2
Change-Id: I33c9f3c471d66c4154be5c2fb5180254401096f0
Reviewed-on: https://review.typo3.org/27731
Reviewed-by: Wouter Wolters
Tested-by: Wouter Wolters
Reviewed-by: Oliver Hader
Tested-by: Oliver Hader