Fix wrong program in yml file and too strict assumption by missing minus sign

The yml file of this task points to the wrong C program, a program that has an overflow, hence causing tools to report an overflow here. During investigation, it was also found that task22-3.c had a missing minus sign in the recently added check that makes this task free of any overflow. Without this fix, the task would still be free of overflows, but be unnecessarily restrictive on the range of input values.

The usual requirements should be fulfilled, as this just fixes the original task.

• programs added to new and appropriately named directory

• license present and acceptable (in machine-readable comment at beginning of program as specified by the REUSE project)

• contributed-by present (either in README file or as comment at beginning of program)

• programs added to a .set file of an existing category, or new sub-category established (if justified)

• suggest to add it to benchmark definitions (.XML) in repositories for benchmark-definitions

• intended property matches the corresponding .prp file

• programs and expected answer added to a .yml file according to task definitions

• data model present in task-definition file
• original (ideally not preprocessed) sources present
• preprocessed files present
• preprocessed files generated with correct architecture
• Makefile added with correct content and without overly broad suppression of warnings