dt-bindings: spmi: spmi-mtk-pmif: Add compatible for MT8189 SoC

dt-bindings: spmi: spmi-mtk-pmif: Add compatible for MT8189 SoC

Add compatible string for the SPMI block on MT8189 SoC, which is
compatible with the one used on MT8195.

Signed-off-by: Louis-Alexis Eyraud <louisalexis.eyraud@collabora.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Link: https://patch.msgid.link/20260123182039.224314-11-sboyd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>