Add Ubuntu 21.04 + stop syncing a few old distros

sql/schema.sql

@@ -259,7 +259,8 @@ INSERT INTO systems (id, name, release, short, relorder) VALUES
   (206,'CentOS',     '7.9',   'centos-7.9',      53),
   (207,'CentOS',     '8.3',   'centos-8.3',      63),
   (208,'FreeBSD',    '12.2',  'freebsd-12.2',    72),
-  (209,'FreeBSD',    '13.0',  'freebsd-13.0',    80);
+  (209,'FreeBSD',    '13.0',  'freebsd-13.0',    80),
+  (210,'Ubuntu',     '21.04', 'ubuntu-hirsute',  33);
 
 
 -- Removes any path components and compression extensions from the filename.

util/centos.sh

@@ -276,7 +276,6 @@ case "$1" in
         $0 8.2
         ;;
     current)
-        $0 6.10 # till 2020-11-30
         $0 7.9  # till 2024-06-30
         $0 8.3  # till 2029-05-31
         ;;

util/fedora.sh

@@ -156,9 +156,9 @@ case "$1" in
         $0 28
         $0 29
         $0 30
+        $0 31
         ;;
     current)
-        $0 31
         $0 32
         $0 33
         ;;

util/ubuntu.sh

@@ -125,6 +125,9 @@ case $1 in
     groovy)
         stdrepo groovy $CMIRROR amd64
         ;;
+    hirsute)
+        stdrepo hirsute $CMIRROR amd64
+        ;;
     old)
         $0 warty
         $0 hoary
@@ -161,6 +164,7 @@ case $1 in
         $0 bionic   # until 2023-04
         $0 focal    # until 2030-04
         $0 groovy   # until 2021-07
+        $0 hirsute  # until 2022-01
         ;;
     all)
         $0 old