OS400/makefile.sh: fix shellcheck warning SC2038 differently #1

Job	Run time
Fuzzing / Build fuzzers	8m 19s
Fuzzing / Determine matrix	4s
Fuzzing / Test i386	8m 40s
Fuzzing / Run fuzzers (curl_fuzzer_https)	3m 8s
Fuzzing / Run fuzzers (curl_fuzzer_gopher)	3m 15s
Fuzzing / Run fuzzers (curl_fuzzer_imap)	3m 6s
Fuzzing / Run fuzzers (curl_fuzzer_file)	2m 50s
Fuzzing / Run fuzzers (curl_fuzzer_http)	3m 11s
Fuzzing / Run fuzzers (curl_fuzzer_ftp)	3m 15s
Fuzzing / Run fuzzers (curl_fuzzer_ldap)	2m 15s
Fuzzing / Run fuzzers (curl_fuzzer_pop3)	3m 18s
Fuzzing / Run fuzzers (curl_fuzzer_rtsp)	3m 8s
Fuzzing / Run fuzzers (curl_fuzzer_mqtt)	3m 11s
Fuzzing / Run fuzzers (curl_fuzzer_smb)	3m 9s
Fuzzing / Run fuzzers (curl_fuzzer_smtp)	3m 15s
Fuzzing / Run fuzzers (curl_fuzzer_tftp)	3m 17s
Fuzzing / Run fuzzers (curl_fuzzer)	3m 1s
Fuzzing / Run fuzzers (curl_fuzzer_ws)	3m 57s
Fuzzing / Run fuzzers (fuzz_url)	2m 59s
Fuzzing / Run fuzzers (curl_fuzzer_bufq)	3m 0s
Fuzzing / Run fuzzers (curl_fuzzer_dict)	3m 10s
	1h 13m 28s

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