arm64: dts: mediatek: mt7622: Add missing pwm-cells to pwm node

stable inclusion
from stable-v5.10.173
commit d7cf3864d781469cb8b323c6d8606890758afaee
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I8BFR3

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d7cf3864d781469cb8b323c6d8606890758afaee



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[ Upstream commit 22925af7 ]

Specify #pwm-cells on pwm@11006000 to make it actually usable.

Fixes: ae457b76 ("arm64: dts: mt7622: add SoC and peripheral related device nodes")
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20221128112028.58021-2-angelogioacchino.delregno@collabora.com


Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>