Merge branch 'ar/fetch-ipversion-in-all'

Merge branch 'ar/fetch-ipversion-in-all'

"git fetch --all --ipv4/--ipv6" forgot to pass the protocol options
to instances of the "git fetch" that talk to individual remotes,
which has been corrected.

* ar/fetch-ipversion-in-all:
  fetch: pass --ipv4 and --ipv6 options to sub-fetches