byteswap.h not found on 12 and 13

Hello all,

I'm getting a file not found on 12 and 13 compiling net/sflowtool latest
update:
It compile fine on 14.

I've searched 14 src and found:
---
./include/byteswap.h
./contrib/ofed/include/byteswap.h
./contrib/llvm-project/libcxx/include/__bit/byteswap.h
---
Any clues?

Thanks,

---
===>  Building for sflowtool-6.01
--- all ---
/usr/bin/make  all-recursive
--- all-recursive ---
Making all in src
--- sflowtool.o ---
cc -DHAVE_CONFIG_H -I. -I..      -O2 -pipe  -fstack-protector-strong
-fno-strict-aliasing -MT sflowtool.o -MD -MP -MF .deps/sflowtool.Tpo -c -o
sflowtool.o sflowtool.c
sflowtool.c:32:10: fatal error: 'byteswap.h' file not found
#include <byteswap.h>
         ^~~~~~~~~~~~
1 error generated.
*** [sflowtool.o] Error code 1
---


-- 
Nuno Teixeira
FreeBSD Committer (ports)