Sync with Git 2.22.1

Author: gitster

.mailmap

@@ -210,6 +210,7 @@ Petr Baudis <pasky@ucw.cz> <pasky@suse.cz>
 Petr Baudis <pasky@ucw.cz> <xpasky@machine>
 Phil Hord <hordp@cisco.com> <phil.hord@gmail.com>
 Philip Jägenstedt <philip@foolip.org> <philip.jagenstedt@gmail.com>
+Philip Oakley <philipoakley@iee.email> <philipoakley@iee.org> # secondary <philipoakley@dunelm.org.uk>
 Philipp A. Hartmann <pah@qo.cx> <ph@sorgh.de>
 Philippe Bruhat <book@cpan.org>
 Ralf Thielow <ralf.thielow@gmail.com> <ralf.thielow@googlemail.com>

Documentation/RelNotes/2.22.1.txt

@@ -143,5 +143,8 @@ Fixes since v2.22
    coding guidelines document did not talk about them and instead had
    a blanket ban against them.
 
+ * The internal diff machinery can be made to read out of bounds while
+   looking for --funcion-context line in a corner case, which has been
+   corrected.
 
 Also contains various documentation updates, code clean-ups and minor fixups.