Fix spell check false positives by ignoring words

The codespell spellchecker tool is used to automatically detect commonly misspelled words in the files of this project.

The misspelled words dictionary was expanded in the latest release of codespell. Some of the text in the project codebase happens to match against newly added entries, which caused codespell to produce false misspelled word detections.

 Since the code that produced the detections is correct and intended, the false positives are resolved by configuring codespell to ignore the problematic words.

Author: per1234

Diff for: .codespellrc

@@ -1,7 +1,7 @@
 # See: https://github.com/codespell-project/codespell#using-a-config-file
 [codespell]
 # In the event of a false positive, add the problematic word, in all lowercase, to a comma-separated list here:
-ignore-words-list = clen,hart,pullrequest
+ignore-words-list = clearin,clen,hart,pullrequest,shiftin,waitin
 builtin = clear
 check-filenames =
 check-hidden =