Merge branch 'jt/clone-guess-remote-head-fix'

"git clone" still gave the message about the default branch name;
this message has been turned into an advice message that can be
turned off.

* jt/clone-guess-remote-head-fix:
  advice: allow disabling default branch name advice
  builtin/clone: suppress unexpected default branch advice
  remote: allow `guess_remote_head()` to suppress advice

diff --cc builtin/clone.c
Simple merge

diff --cc builtin/fetch.c
Simple merge

diff --cc refs.c
Simple merge

diff --cc remote.c
Simple merge