Broaden compatibility amount Win32 headers even further [some don't have

SIZE_T].

crypto/rand/rand_win.c

@@ -168,7 +168,7 @@ typedef DWORD (WINAPI *GETQUEUESTATUS)(UINT);
 
 typedef HANDLE (WINAPI *CREATETOOLHELP32SNAPSHOT)(DWORD, DWORD);
 typedef BOOL (WINAPI *CLOSETOOLHELP32SNAPSHOT)(HANDLE);
-typedef BOOL (WINAPI *HEAP32FIRST)(LPHEAPENTRY32, DWORD, SIZE_T);
+typedef BOOL (WINAPI *HEAP32FIRST)(LPHEAPENTRY32, DWORD, size_t);
 typedef BOOL (WINAPI *HEAP32NEXT)(LPHEAPENTRY32);
 typedef BOOL (WINAPI *HEAP32LIST)(HANDLE, LPHEAPLIST32);
 typedef BOOL (WINAPI *PROCESS32)(HANDLE, LPPROCESSENTRY32);