support cosa buildextend-nvidiabluefield

I had planned not to add this legacy symlink because
this is a net new artifact nothing should be using it,
but there is logic today [1] that attempts to distinguish
between "stable" and "experimental" osbuild artifacts based
on the symlink.

For now I think we should keep that logic around because
there are still a few artifacts that don't use OSBuild.

[1] https://github.com/coreos/fedora-coreos-pipeline/blob/0266a4a14b3c9f947255cc5284d399dec4077f03/utils.groovy#L470-L495

Author: dustymabe

cmd/coreos-assembler.go

@@ -14,7 +14,7 @@ import (
 // commands we'd expect to use in the local dev path
 var buildCommands = []string{"init", "fetch", "build", "osbuild", "run", "prune", "clean", "list"}
 var advancedBuildCommands = []string{"import", "buildfetch", "buildupload", "oc-adm-release", "push-container"}
-var buildextendCommands = []string{"aliyun", "applehv", "aws", "azure", "digitalocean", "exoscale", "gcp", "hyperv", "ibmcloud", "kubevirt", "live", "metal", "metal4k", "nutanix", "openstack", "oraclecloud", "qemu", "secex", "virtualbox", "vmware", "vultr"}
+var buildextendCommands = []string{"aliyun", "applehv", "aws", "azure", "digitalocean", "exoscale", "gcp", "hyperv", "ibmcloud", "kubevirt", "live", "metal", "metal4k", "nutanix", "nvidiabluefield", "openstack", "oraclecloud", "qemu", "secex", "virtualbox", "vmware", "vultr"}
 
 var utilityCommands = []string{"aws-replicate", "coreos-prune", "compress", "copy-container", "diff", "koji-upload", "kola", "push-container-manifest", "remote-build-container", "remote-session", "sign", "tag", "update-variant"}
 var otherCommands = []string{"shell", "meta"}

src/cmd-buildextend-nvidiabluefield

@@ -0,0 +1 @@
+./cmd-osbuild