Log Message:
alsa-lib: update to 1.2.12.

Switch from 'c99' to 'c' in USE_LANGUAGES: c99 is not used
by the build system, and when forced using FORCE_C_STD,
the build fails.

Changes:

Core

    Release v1.2.12
    GitHub Actions: Use actions/checkout@v4
    pcm: plug - add automatic conversion for iec958 subframe samples

PCM API

    pcm: extend doc for snd_pcm_hw_params_get_sbits()
    pcm: clarify and fix default sbits (msbits) value for all formats
    pcm: ladspa - Skip missing ladspa directories
    pcm: snd_pcm_(physical_)format_width() - change documentation
    pcm: plug - add automatic conversion for iec958 subframe samples

PCM Plugin API

    pcm: plug - add automatic conversion for iec958 subframe samples

Topology API

    topology: correct version script path

Use Case Manager API

    use-case.h: add DisplayPort to HDMI device description
    ucm: doc - add Variant and Macro to the evaluation order
    ucm: define and describe Syntax 7
    ucm: raise error when macro argument is already defined (used)
    ucm: do argument value substitution for Macros
    ucm: fix Path condition - substitute Path
    ucm: fix Path condition - substitute Path and Mode fields

Async helpers

    async: snd_async_del_handler - move clear signal using sigaction as last

Configuration

    conf: aliases: hdmi: Include unconditionally the
    conf: USB-Audio: Add Corsair HS60 Pro to the IEC958 blacklist
    conf: USB-Audio: Add more Scarlett devices to the IEC958 blacklist

Test/Example code

    tests: latency.c - fix copy-n-paste typos (sw -> hw params) in error messages