doc: restore: remove note on --patch w/ pathspecs

doc: restore: remove note on --patch w/ pathspecs

This note was added to the restore command docs in 46e91b663b
(checkout: split part of it to new command 'restore', 2019-04-25),
but it is now inaccurate. The underlying builtin `add -i` implementation,
made default in 0527ccb1b5 (add -i: default to the built-in implementation,
2021-11-30), supports pathspecs, so `git restore -p <pathspec>...` has
worked for all users since then. I bisected to verify this was the commit
that added support.

Signed-off-by: Adam Johnson <me@adamj.eu>
Acked-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>