Fix crash on particular LCMS profiles
Before this commit, Krita would crash on particular LCMS profiles because they were saying that they contain definition of white point ("cmsIsTag") but later the pointer that "cmsReadTag" returned was empty. This commit makes sure that even if the pointer is empty, Krita won't crash.
- download lcms profiles from the bug report https://bugs.kde.org/show_bug.cgi?id=423685
- put them in your resource folder/profiles (create the folder if it doesn't exists)
- open Krita (it should open; it won't open on Krita 4.3.0 for example)
- make sure all profiles are there
- I confirmed this builds.
- I confirmed Krita ran and the relevant functions work.
- I tested the relevant unit tests and can confirm they are not broken. (If not possible, don't hesitate to ask for help!)
- I made sure my commits build individually and have good descriptions as per KDE guidelines.
- I made sure my code conforms to the standards set in the HACKING file.
- I can confirm the code is licensed and attributed appropriately, and that unattributed code is mine, as per KDE Licensing Policy.