[UCRT] Fix multiple missing dereferences

This is a bug in MS UCRT code. MSVC allows to check a pointer to be > 0, GCC emits a warning.

[UCRT] Import Microsoft.Windows.SDK.CRTSource version 10.0.22621.3

Imported from https://www.nuget.org/packages/Microsoft.Windows.SDK.CRTSource/10.0.22621.3
License: MIT