perl: fix CVE-2020-12723

Minor changes to the test cases count in the .patch file to make it
align with current version, so the fixes can be apply.
Changes apply to line:
https://github.com/perl/perl5/commit/66bbb51b93253a3f87d11c2695cfb7bdb782184a#diff-e31ddd69cf47acf02911647c691a0283L28



Signed-off-by: Lee Chee Yang <chee.yang.lee@intel.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>