MAINTAINERS: ARM: airoha: add entry to cover Airoha SoC

MAINTAINERS: ARM: airoha: add entry to cover Airoha SoC

Airoha SoC is not covered by any maintainer entry so relevant patches
can be missed.  It seems Mediatek SoC maintainers were covering some
parts of Airoha and Airoha itself is subsidiary of Mediatek, so assign
the Airoha maintenance to Matthias and AngeloGioacchino.

Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20240628095044.132276-2-angelogioacchino.delregno@collabora.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>