Bug: `PWL file=*.wav` prevents `.func` resolution in behavioral source

I wrote unofficial guidelines and upload to my Github. This particular slide can be found in Device Guideline, V-Source section.
https://github.com/KSKelvin-Github/Qspice/blob/main/Guideline/README.md

Since you work on .wav file, just in case you not aware Listen to Trace feature yet.
https://forum.qorvo.com/t/where-has-the-opportunity-to-listen-to-signals-disappeared/24767/2