Fixed OMP falsely declared private variables

What is the bug

OpenMP optimization determines the values of i_startblk and i_endblk on its own instead of the value passed in the subroutine

How do you fix it

Removed the inclusion of i_startblk and i_endblk as private variables while starting an OMP parallel construct. It was redundant anyway.

How urgent is the bugfix

• I need it as soon as possible
• I can wait for a couple of days
• None of my current codes is directly affected

Mandatory steps before review

• Gitlab CI passes (Hint: use make format for linting)
• Bugfix is covered by additional unit tests
• Mark the merge request as ready by removing Draft:

Mandatory steps before merge

• Reviewed by a maintainer
• Incorporate review suggestions
• Remember to edit the commit message and select the proper changelog category (feature/bugfix/other)
• Prior to merging, please remove any boilerplate from the MR description, retaining only the What is the bug and How do you fix it section to maintain

You are not supposed to merge this request by yourself, the maintainers of libiconmath take care of this action!