[PATCH 0/1] MR7633: win32u: Fixed the sign error in the conversion from FIXED to FT_Fixed

[Yeshun Ye (＠yeyeshun)]

If the `FT_MULFIX_ASSEMBLER` macro is not used during the compilation of FreeType,    
unsigned extension to `FT_Fixed` will cause `FT_MulFix` to produce incorrect results.

The usage of the attached code is for compilation with GCC on x86_64.     
Toggling the `FT_MULFIX_ASSEMBLER` macro will produce different results.    
demo: [main.c](/uploads/18e77f790be1cb5acf2ef8f52b61bf39/main.c)    
Signed-off-by: YeshunYe