distro: Update bootstrap binaries to an nscd-less libc.
Update bootstrap binaries following changes in commit d3b5972 ("Build
glibc without nscd, and with static NSS modules.")
* Makefile.am (distro/packages/bootstrap/x86_64-linux/guile-2.0.7.tar.xz,
distro/packages/bootstrap/i686-linux/guile-2.0.7.tar.xz): Update hashes.
* build-aux/download.scm (file-name->uri): Update URL.
* distro/packages/bootstrap.scm (%bootstrap-coreutils&co,
%bootstrap-binutils, %bootstrap-glibc, %bootstrap-gcc): Update URLs
and hashes.
79580eb698