* Latest Amazon Linux enables 64bid when creating ext4 partitions, which is incompatible with syslinux/extlinux bootloader. Explicitly disable 64bit support, as it's highly unlikely we'll need a boot volume >16 TiB.
* update-extlinux.conf - switch kernel default to 'virt', as 'hardened' no longer exists.
* standardize on 'linux-virt' kernel
+ no longer need 'kernel_flavor' variable
+ always install 'aws-ena-driver' package
+ always enable ena_support
* switch to 'variables.yaml' for config
+ update build/convert script to stringify certain keys that may contain arrays
+ copy from 'variables.yaml-default' if it doesn't exist
* drop 'vpc' variable, using 'subnet' derives the proper VPC to use
* fix chrony.conf (all pool.ntp.org references are changed to 169.254.169.123)
* update README.md caveats
* README.md
+ update list of modern instance types
+ add caveat regarding linux-vanilla vs. linux-virt
* alpine-ami.yaml
+ build instance type is always t3.nano
+ block device where we build is always /dev/xvdf
+ add optional AMI encryption
+ always enable AMI SR-IOV flag (vanilla & virt both have the necessary driver)
+ no need to pass volume_name to make_ami.sh
* make_ami.sh
+ replace hard tabs with 4 spaces
+ always set up edge repositories
+ no need to add mkinitfs package, it's a dependency of linux-*
+ fix update of /etc/inittab
+ fix configuration of NTP
+ declare local vars in main()
+ device is always /dev/xvdf
* variables.json-default/example
+ improve comment for kernel_flavor
+ default add_repos is now empty
+ remove acct & e2fsprogs-extra from add_pkgs
+ add optional AMI encryption
+ remove sriov_enable, build_instance_type, and volume_name vars
* move config variables from alpine-ami.yaml to variables.json-*
+ variables.json-default - ready-for-action original default config
+ variables.json-example - original defaults with comments
* clean up tabs vs. spaces in make_ami.sh
* make_ami.sh handles custom kernel flavor, extra repos, and extra packages
* tweak README with regards to aws-ena-driver caveat
* add public_ip variable, setting to 'true' allows packer to build from outside AWS
* use smallest instance_type (t2.nano) and volume_size (1 GiB)
* eu-west-3 region is live; ap-northeast-3 requires subscription
* no longer need setup_staging_repos function...
+ tiny-ec2-bootstrap is available in main since v3.8
+ aws-ena-driver-vanilla is only available in edge/testing
* switched to linux-vanilla since linux-hardened is no longer available and linux-virt does not have NVME available
+ TODO? make kernel choice selectable (significant memory/disk savings linux-virt can be used)
Jake Buchholz