include bh_platform.h (#4135)

This should guarantee that the various macros required by
wasm_proposal.c are defined even if the build system does not supply
them to the compiler command.

product-mini/platforms/common/wasm_proposal.c

@@ -5,6 +5,8 @@
 
 #include <stdio.h>
 
+#include "bh_platform.h"
+
 void
 wasm_proposal_print_status(void)
 {