build: allow bootstrap on fresh checkout again
build: allow bootstrap on fresh checkout again

* autogen.sh: Fix omission from last commit.

Signed-off-by: Eric Blake <a9da18479c871fe903d9590822cfe2629c6a4d11@redhat.com>

battlemidget/deprecated-mingw32-netcf,seanbruno/fbsd-netcf,emaste/netcf,osier/netcf,osier/netcf,hallyn/netcf,osier/netcf,emaste/netcf,seanbruno/fbsd-netcf,seanbruno/fbsd-netcf,hallyn/netcf,hallyn/netcf,battlemidget/deprecated-mingw32-netcf,emaste/netcf