Can not update firmware with the latest connectivity kit

[Jean-Baptiste Boric]

I ran tests inside LXC containers and I've found why it won't work on Ubuntu 14.04.

The Makefile macros I'm using do not work properly with GNU make 3.81: LIST_SRCS in particular returns nothing, hence why the generated PRIME_OS.ROM was empty. osrom2elf built properly because it does not use macros in its Makefile.

It does work under Ubuntu 16.04, which has GNU make 4.1, so building probably requires GNU Make >= 4.0.

WSL recently switched to Ubuntu 16.04 but pre-existing installations are not upgraded automatically. Either recreate your WSL installation (lxrun /uninstall; lxrun /install) or execute do-release-upgrade to update your Ubuntu installation to 16.04.