Remove legacy for arm64, put notification

Experiencing kernel panics loading legacy installers,
where Subiquity tests fine on Packet.  Dropping the arm64
legacy code I added and putting a notice to use 20.04 and up
for arm64 builds using the Subiquitty installer

CHANGELOG.md

@@ -5,8 +5,10 @@ All notable changes to this project will be documented in this file.
 ## [Unreleased]
 
 ## [2.0.49]
+#### Added
+- Support for Ubuntu 20.04 Subiquity and up on arm64
 
-## [2.0.48]
+## [2.0.48] 2021-09-17
 #### Added
 - Support for Harvester
 - Support for Tails

roles/netbootxyz/defaults/main.yml

@@ -593,8 +593,6 @@ releases:
     menu: linux
     mirror: http://archive.ubuntu.com
     name: Ubuntu
-    ports_dir: ubuntu-ports
-    ports_mirror: http://ports.ubuntu.com
     versions:
     - code_name: hirsute
       name: 21.04 Hirsute Hippo

roles/netbootxyz/templates/menu/ubuntu.ipxe.j2

@@ -29,6 +29,7 @@ iseq ${ubuntu_version} focal && set install_type sub ||
 iseq ${ubuntu_version} hirsute && set install_type sub ||
 iseq ${ubuntu_version} focal-legacy && set ubuntu_version focal ||
 iseq ${install_type} sub && goto boot_type ||
+iseq ${os_arch} arm64 && echo "arm64 not supported on legacy network installs, please use 20.04 Subiquity and up" && sleep 5 && goto ubuntu ||
 goto mirrorcfg
 
 :older_release
@@ -42,11 +43,8 @@ goto boot_type
 
 :mirrorcfg
 set mirrorcfg mirror/suite=${ubuntu_version}
-iseq ${os_arch} arm64 && set ubuntu_mirror {{ releases.ubuntu.ports_mirror }} ||
-iseq ${os_arch} amd64 && set dir ${ubuntu_base_dir}/dists/${ubuntu_version}-updates/main/installer-${os_arch}/current/images/netboot/ ||
-iseq ${os_arch} amd64 && iseq ${ubuntu_version} focal && set dir ${ubuntu_base_dir}/dists/${ubuntu_version}-updates/main/installer-${os_arch}/current/legacy-images/netboot/ ||
-iseq ${os_arch} arm64 && set dir {{ releases.ubuntu.ports_dir }}/dists/${ubuntu_version}-updates/main/installer-${os_arch}/current/images/netboot/ ||
-iseq ${os_arch} arm64 && iseq ${ubuntu_version} focal && set dir {{ releases.ubuntu.ports_dir }}/dists/${ubuntu_version}-updates/main/installer-${os_arch}/current/legacy-images/netboot/ ||
+set dir ${ubuntu_base_dir}/dists/${ubuntu_version}-updates/main/installer-${os_arch}/current/images/netboot/
+iseq ${ubuntu_version} focal && set dir ${ubuntu_base_dir}/dists/${ubuntu_version}-updates/main/installer-${os_arch}/current/legacy-images/netboot/ ||
 goto boot_type
 
 :boot_type