cannode: safety_button: fix compatibility with Ardupilot #26362

Job	Run time
build (check_format)	1m 1s
build (check_newlines)	1m 26s
build (tests)	5m 40s
build (tests_coverage)	7m 24s
build (px4_fmu-v2_default stack_check)	3m 14s
build (validate_module_configs)	47s
build (shellcheck_all)	1m 24s
build (NO_NINJA_BUILD=1 px4_fmu-v5_default)	4m 5s
build (NO_NINJA_BUILD=1 px4_sitl_default)	3m 16s
build (px4_sitl_allyes)	4m 15s
build (airframe_metadata)	51s
build (module_documentation)	54s
build (parameters_metadata)	1m 1s
	35m 18s

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