Mismatch Between win32syscalls.h and Windows System Call Numbers

[zhengxianwei]

The APIs and call numbers in win32syscalls.h don't seem to match those in
the Windows system.

NtGdiAlphaBlend is listed as 4 in win32syscalls.h, but in reality, it's
0x1075 in win32u.dll on Windows 11.

So are these values user-defined?