[CMAKE] Fix host tools build on x86-64 mingw

Dynamically check for sys/types.h and pid_t in wine config.h
Use TARGET_xxx defines instead of _X86_ as this is undefined by GCC
Add some sense in include directories management by using interface
libraries

sdk/tools/unicode/CMakeLists.txt

@@ -83,7 +83,8 @@ list(APPEND SOURCE
     wctomb.c
     wctype.c)
 
-add_library(unicode ${SOURCE})
+add_library(unicode STATIC ${SOURCE})
+target_link_libraries(unicode PRIVATE host_includes)
 
 if(MSVC)
     # Disable warning "'<': signed/unsigned mismatch"