ALSA: hda/realtek: Enable Mute LED on HP 840 G8 (MB 8AB8)

On my EliteBook 840 G8 Notebook PC (ProdId 5S7R6EC#ABD; built 2022 for
german market) the Mute LED is always on. The mute button itself works
as expected. alsa-info.sh shows a different subsystem-id 0x8ab9 for
Realtek ALC285 Codec, thus the existing quirks for HP 840 G8 don't work.
Therefore, add a new quirk for this type of EliteBook.

Signed-off-by: Hans Peter <flurry123@gmx.ch>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20240219164518.4099-1-flurry123@gmx.ch
Signed-off-by: Takashi Iwai <tiwai@suse.de>