obj: object header is no longer allocated automatically

include/socks/kext.h

@@ -2,6 +2,7 @@
 #define SOCKS_KEXT_H_
 
 #include <socks/status.h>
+#include <socks/object.h>
 #include <socks/compiler.h>
 #include <socks/btree.h>
 
@@ -69,6 +70,7 @@ struct kext_info {
 };
 
 struct kext {
+	struct object k_base;
 	enum kext_flags k_flags;
 	char k_ident[KEXT_IDENT_MAX];
 	uint64_t k_ident_hash;