MAINTAINERS: update ASoC/Intel/SOF maintainers

Keyon Jie was a key contributor to the Intel ASoC and SOF Intel
drivers, but he's moved on to a different role within Intel. We wish
him all the best in his new endeavors.

Bard Liao, Kai Vehmanen, Ranjani Sridharan and Peter Ujfalusi have
been involved in the Intel multi-maintainer team, it's time to update
the MAINTAINERS entry to reflect their contributions and clarify their
role.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com>
Link: https://lore.kernel.org/r/20220610214313.42903-1-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>