[scripts] only use garr.it and pkg.sabayon.org as package mirrors during ISO build

scripts/remaster_generic_inner_chroot_script.sh

@@ -1,3 +1,8 @@
 #!/bin/sh
 export FORCE_EAPI=2
 equo update || ( sleep 1200 && equo update ) || exit 1
+
+# disable all mirrors but GARR
+sed -n -e "/pkg.sabayon.org/p" -e "/garr.it/p" -e "/^branch/p" \
+	-e "/^product/p" -e "/^official-repository-id/p" -e "/^differential-update/p" \
+	-i /etc/entropy/repositories.conf

scripts/remaster_generic_inner_chroot_script_after.sh

@@ -312,6 +312,9 @@ rm /var/lib/entropy/client/database/*/sabayonlinux.org -rf
 rm /var/lib/entropy/client/database/*/sabayon-weekly -rf
 equo rescue vacuum
 
+# restore original repositories.conf (all mirrors were filtered for speed)
+cp /etc/entropy/repositories.conf.example /etc/entropy/repositories.conf || exit 1
+
 # cleanup log dir
 rm /var/lib/entropy/logs -rf