don't include GNU/Linux definitions of FD_*

since they're provided by lwip, as seen in sys/types.h

modules/Makefile

@@ -129,6 +129,10 @@ ifneq (,$(filter $(HARDWARE),bt6707 bt6709))
 		CFLAGS += -DWOLFSSH_NO_TIMESTAMP
 	endif
 endif
+
+# don't include GNU/Linux definitions of FD_* since they're provided by lwip, as seen in sys/types.h
+CFLAGS += -D__USE_W32_SOCKETS
+
     CSRC += $(wildcard HTTP_Server/trap_params.c)
     CSRC += $(wildcard HTTP_Server/web_params_api.c)
     CSRC += $(wildcard ../thirdparty/lwip_patched/src/*.c)