CentOS build for armv6 and armv7 fail

[pschmitt]

See:

• https://github.com/pschmitt/zabbix-docker-multiarch/runs/510625533?check_suite_focus=true

• zabbix-docker-multiarch/build.sh

  Lines 55 to 58 in 2978418

  	if [[ "$OS" == "centos" ]]
  	then
  	# grep -vE 'ppc64le|s390x|arm/v6|arm/v7' <<< "$all_archs"
  	grep -vE 'arm/v6|arm/v7' <<< "$all_archs"