Refactored pandas_timedelta_to_timedeltastruct (pandas-dev#55999)

* Refactored pandas_timedelta_to_timedeltastruct

* use generic macros

* Revert "use generic macros"

This reverts commit 29d115d.

* fix sign issue

* wextra fixes

* more wextra

* remove extraneous parantheses

Author: WillAyd