to also include tools and scripts like objtool, which are now needed for
external module building
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
with libraries that are not GPL-2-only compatible, fix previously typoed
variable, and add build-dep on libiberty-dev for CPLUS demangling.
Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>