From: Philippe Blain <levraiphilippeblain@gmail.com>

The 'linkgit' Asciidoc macro is misspelled as 'linkit' in the
description of 'GIT_SEQUENCE_EDITOR' since the addition of that variable
to git(1) in 902a126eca (doc: mention GIT_SEQUENCE_EDITOR and
'sequence.editor' more, 2020-08-31).

Fix that.

Signed-off-by: Philippe Blain <levraiphilippeblain@gmail.com>

Submitted-As: https://lore.kernel.org/git/pull.934.git.git.1608651140403.gitgitgadget@gmail.com