added comments on variables

bootstrap-bookworm.sh

@@ -41,7 +41,7 @@ netDNS2="198.51.100.10"
 netNTP="pool.ntp.org"
 pwdAdmin=""                         # "" blank for auto-generation
 pwdRoot=""                          # "" blank for auto-generation
-extraPackages="qemu-guest-agent"    # additional packages to install
+extraPackages="qemu-guest-agent"    # additional packages to install, e.g. cryptsetup
 
 # Overwrite default variables from config file
 [ -f ./config.sh ] && source config.sh