MAINTAINERS: Update entry for MediaTek SoC support

The linux-mediatek IRC channel has moved to liber.chat for quite some
time. Apart from that, not all patches are also send to LKML, so add
this ML explicitly.

And last but not least:
Angelo does a wunderfull job in reviewing patches for all kind of
devices from MediaTek.

Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>
Link: https://lore.kernel.org/r/20230201152256.19514-1-matthias.bgg@kernel.orgSigned-off-by: Arnd Bergmann <arnd@arndb.de>

MAINTAINERS

@@ -2452,11 +2452,14 @@ F:	drivers/rtc/rtc-mt7622.c
 
 ARM/Mediatek SoC support
 M:	Matthias Brugger <matthias.bgg@gmail.com>
+R:	AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
+L:	linux-kernel@vger.kernel.org
 L:	linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
 L:	linux-mediatek@lists.infradead.org (moderated for non-subscribers)
 S:	Maintained
 W:	https://mtk.wiki.kernel.org/
-C:	irc://chat.freenode.net/linux-mediatek
+C:	irc://irc.libera.chat/linux-mediatek
+F:	arch/arm/boot/dts/mt2*
 F:	arch/arm/boot/dts/mt6*
 F:	arch/arm/boot/dts/mt7*
 F:	arch/arm/boot/dts/mt8*
@@ -2464,7 +2467,7 @@ F:	arch/arm/mach-mediatek/
 F:	arch/arm64/boot/dts/mediatek/
 F:	drivers/soc/mediatek/
 N:	mtk
-N:	mt[678]
+N:	mt[2678]
 K:	mediatek
 
 ARM/Mediatek USB3 PHY DRIVER