bib should not generate ami image on s390x machine

[chunfuwen]

Since in AWS, it doesn't support s390x guest. Therefore it make sense it remind us that bib can not generate ami disk image format on s390x machine

sudo podman run --rm -it --privileged --pull=newer --security-opt label=type:unconfined_t -v /var/lib/libvirt/images/output:/output -v /var/lib/libvirt/images/config.json:/config.json   -v /var/lib/libvirt/images/auth.json:/run/containers/0/auth.json  quay.io/centos-bootc/bootc-image-builder:latest  --type ami --tls-verify=false  --config /config.json  quay.io/centos-bootc/centos-bootc:stream9 

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⏱  Duration: 11s
manifest - finished successfully
build:    	ac3f8e47f57148704d7a39bfe769dfa72b8234cf58d8199c295530c637f70418
image:    	80a71d6ea497bddadfcd93a67f0384a70bf1fe2cbb622fb6c8429ddec7027ddd
qcow2:    	1116c2a19eb0fccc454a300dbae2ce081acdf096819901eb32505ff82d02ee33
vmdk:     	220fe8103e71700a49ce63234deffa7f24ba965a44a3df9c4c3537204235f20e
vpc:      	d11f1af87e5085a2da7cf4d41aef26c921e30f4a39f91f883ab86ba805e4e850
ovf:      	29cf016cb4c8e5aabe50c4c51b19cf8ffd728437339240b341ceac16a0d8004b
archive:  	efe764cc9d5b002a66b8743d289b603d03ddcd9beaea16ff388bb54a70d654d8
gce:      	ac21da7d9310b6096c69bc1d7b2b8caefdb8303254c218bfa7969fe84e643ba3
Build complete!
Results saved in

[achilleas-k]

We should have a type-architecture matrix like we have in osbuild-composer for this. Though, in this particular case, the ami is the same as the raw image, and I think a raw disk image for s390x might be okay to keep.

[chunfuwen]

We already has supported raw disk image using --raw option. Although ami implicitly generate raw disk image, it is more likely to give user impression that s390x guest can be supported as EC2 instance in AWS platform since we support importing an AMI into AWS account when generating ami image