Some commits missed to update the patch file, so we're catching up on
this.
To generally make this easier, we back-port generate_patch.sh from
PHP-7.4, where we now also generate magic.h from magic.h.in.
This simplifies the libmagic patch:
- in upstream the HAVE_STRERROR check has been removed
- in upstream library the HAVE_SIGNAL_H has been removed
- indentations syncs with the upstream library
- some irrelevant changes removed from the patch (log comment), upstream
has this correctly logged already so no need to patch the comment.
Closes GH-4298