OS400/makefile.sh: fix shellcheck warning SC2038 differently

Reported-by: Patrick Monnerat
Bug: curl#19451 (comment)
Follow-up to af5a164 curl#19451

Closes curl#19482

Author: vszakats

packages/OS400/makefile.sh

@@ -35,7 +35,10 @@ cd "${TOPDIR}" || exit 1
 
 #       Make sure all files are UTF8-encoded.
 
-find "${TOPDIR}" -type f -print0 | xargs -0 ls -S -- | while read -r CCSID FILE
+# Qshell does not support -print0. ls -S has a non-POSIX meaning.
+#   https://www.ibm.com/docs/en/i/7.1.0?topic=qshell-command-language
+# shellcheck disable=SC2038
+find "${TOPDIR}" -type f | xargs ls -S -- | while read -r CCSID FILE
 do      if [ "${CCSID}" != 1208 ]
         then    CMD="CPY OBJ('${FILE}') TOOBJ('${FILE}') FROMCCSID(*OBJ)"
                 CMD="${CMD} TOCCSID(1208) DTAFMT(*TEXT) REPLACE(*YES)"