devel/sobjectizer: update the port to version 5.8.3

• Switch to the official (static) .tar.xz release tarball
• Earlier 5.8.1.x releases had been skipped due to some build issues (can't recall whether it was with the port or its consumers) which no longer exhibit themselves
• Bump dependencies in the `net/arataga' port accordingly

Reported by: portscout