Workaround is not needed for etcnet> = 0.9.19.1-alt1
See also commit 8a299b4a

Otherwise, the automatic loading of the iso starts without the ability to set
the loading of another.

See also commit: 61f66b08

- If the BRANCH variable is not empty, and the BRANDING variable on
  the contrary is empty, then BRANDING is assigned to alt-starterkit.
- Revert commit "base+rescue: add eepm"
- Fixed conditions with variable BRANCH
- Drop STARTERKIT variable
- grub: add submenu "Network installation"
- Do not use udev-rule-generator-net in regulars/starterkits
- initrd-bootchain: Initial feature
- stage1: allow creating stage1 without stage2
- ntp: fix add fallbck THE_NTPD_SERVICE
- Makefile: check *_PACKAGES* variables as lists
- vmguest: fix build with use/vmguest/kvm/x11 for BRANCH=p9
- grub, syslinux: replace 'splash=0' to 'nosplash' in rescue
- drop features: aarch64-dbm, armh-cubox, armh-dovefb, nexus7,
  armh-tegra, armh
- build-vm: add FEATURES and MODULES_TRY_ADD from /etc/initrd.mk
- syslinux: Generate isolinux.cfg for any BOOTLOADER
- build-vm, stage2: set GLOBAL_HSH_PROC=1
- vm.mk: Add sr_mod to initrd modules for vm/cloud-system
  (thanks obirvalger@)

isolinux.cfg required for alterator-netinst.