…in default (#17459)

* sapi/cli: Extend `--ini` to print INI settings changed from the builtin default

This is intended to make it easier to check whether or not a given INI setting
is changed from the default when building reproducers for a bugreport, without
forgetting any that might be relevant to the report.

As an example, running `sapi/cli/php -c /etc/php/8.3/cli/ --ini` on my Ubuntu
will now output:

    Configuration File (php.ini) Path: /usr/local/lib
    Loaded Configuration File:         /etc/php/8.3/cli/php.ini
    Scan for additional .ini files in: (none)
    Additional .ini files parsed:      (none)

    Non-standard INI settings:
    allow_url_include: "0" -> ""
    auto_append_file: (none) -> ""
    auto_prepend_file: (none) -> ""
    display_errors: "1" -> ""
    display_startup_errors: "1" -> ""
    enable_dl: "1" -> ""
    error_reporting: (none) -> "22527"
    html_errors: "1" -> "0"
    ignore_repeated_errors: "0" -> ""
    ignore_repeated_source: "0" -> ""
    implicit_flush: "0" -> "1"
    log_errors: "0" -> "1"
    mail.add_x_header: "0" -> ""
    mail.mixed_lf_and_crlf: "0" -> ""
    max_execution_time: "30" -> "0"
    memory_limit: "128M" -> "-1"
    request_order: (none) -> "GP"
    session.cookie_httponly: "0" -> ""
    session.gc_divisor: "100" -> "1000"
    session.gc_probability: "1" -> "0"
    session.sid_bits_per_character: "4" -> "5"
    session.sid_length: "32" -> "26"
    short_open_tag: "1" -> ""
    unserialize_callback_func: (none) -> ""
    user_dir: (none) -> ""
    variables_order: "EGPCS" -> "GPCS"
    zend.assertions: "1" -> "-1"
    zend.exception_ignore_args: "0" -> "1"
    zend.exception_string_param_max_len: "15" -> "0"

* Improve phrasing

Co-authored-by: Michael Voříšek <[email protected]>

* NEWS/UPGRADING

---------

Co-authored-by: Michael Voříšek <[email protected]>

Fixes oss-fuzz #391975641
Closes GH-17620

* PHP-8.4:
  Fix segfault when assigning to backing value by-ref from hook