libxkbfile: upgrade 1.1.3 -> 1.2.0

libxkbfile: upgrade 1.1.3 -> 1.2.0

Changelog:
  - libxkbfile is used by the X servers and utilities to parse the XKB
    configuration data files.
  - This release adds a new XkbRF_FreeVarDefs() API, and brings over many
    fixes from the other copies of XKB code in the various X.Org repos.
  - Since no complaints were received about the added meson build system
    in the 1.1.3 release (February 2024), the autoconf build system has been
    removed in this release.

Ref: [https://lists.x.org/archives/xorg-announce/2026-January/003662.html]

Signed-off-by: Zhang Peng <peng.zhang1.cn@windriver.com>
Signed-off-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
Signed-off-by: Ross Burton <ross.burton@arm.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>