GoPro H11/12 upload fails at 4GB with ptp2 driver

[mijoost]

Latest GoPro models (HERO12/11) split videos at ~12GB chunks/chapters on large (64GB and above) SD cards.
File listing in gphoto2 limits the size at 4GB, and uploading with libgphoto2-2.5.31 truncates those files at 4GB, effectively corrupting them (missing important index info at the end).

There used to be a related issue:
#582
but somehow that fix is not effective here (2.5.31).

I created a proof-of-concept patch to fix this issue against libgphoto2-2.5.31, which corrects both the displayed file sizes and the truncated uploading.
This small patch "works for me"(TM), but hasn't been checked for possible side-effects.
May the wizards have a look, and take, modify or create something else to the same effect.
libgphoto2-2.5.31.gopro_64.patch