ALSA: hda/realtek: Enable mute LED on HP EliteBook 840 G6

The HP EliteBook 840 G6 (PCI SSID 103c:854d) has an ALC215 codec whose
mic-mute and audio-mute LEDs are wired to the same GPIOs as the already
supported EliteBook 830 G6 and 840 G7. Without a matching quirk the LEDs
are never registered, so the front-panel mic-mute LED stays permanently
lit and does not track the mute state.

Apply ALC285_FIXUP_HP_GPIO_LED, mirroring the sibling EliteBook entries.
With this fixup the codec registers an "hda::micmute" LED class device and
the LED correctly follows the capture-mute state. This was verified on the
affected machine by forcing the same fixup at runtime via
snd_sof_intel_hda_generic.hda_model=103c:8548, which made the LED work as
expected.

Signed-off-by: Ramcharan Rajpurohit <b23ci1032@iitj.ac.in>
Link: https://patch.msgid.link/20260619062435.26256-1-b23ci1032@iitj.ac.in
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Author: RamcharanRajpurohit

sound/hda/codecs/realtek/alc269.c

@@ -6987,6 +6987,7 @@ static const struct hda_quirk alc269_fixup_tbl[] = {
 	SND_PCI_QUIRK(0x103c, 0x8537, "HP ProBook 440 G6", ALC236_FIXUP_HP_MUTE_LED_MICMUTE_VREF),
 	SND_PCI_QUIRK(0x103c, 0x8548, "HP EliteBook x360 830 G6", ALC285_FIXUP_HP_GPIO_LED),
 	SND_PCI_QUIRK(0x103c, 0x854a, "HP EliteBook 830 G6", ALC285_FIXUP_HP_GPIO_LED),
+	SND_PCI_QUIRK(0x103c, 0x854d, "HP EliteBook 840 G6", ALC285_FIXUP_HP_GPIO_LED),
 	SND_PCI_QUIRK(0x103c, 0x856a, "HP Pavilion 15-cs1xxx", ALC295_FIXUP_HP_PAVILION_MUTE_LED_1B),
 	SND_PCI_QUIRK(0x103c, 0x85c6, "HP Pavilion x360 Convertible 14-dy1xxx", ALC295_FIXUP_HP_MUTE_LED_COEFBIT11),
 	SND_PCI_QUIRK(0x103c, 0x85de, "HP Envy x360 13-ar0xxx", ALC285_FIXUP_HP_ENVY_X360),