Remove unused `#include`s from parser/cutils.c
Looks like these have been unused since 7c665f9c.
- are either individually buildable or squashed
have commit messages which describe what they do
(referring to Notes and tickets using
#NNNNsyntax when appropriate)
- have added source comments describing your change. For larger changes you likely should add a Note and cross-reference it from the relevant places.
- add a testcase to the testsuite.
- replace this message with a description motivating your change
If you have any questions don't hesitate to open your merge request and inquire
in a comment. If your patch isn't quite done yet please do add prefix your MR