dt-bindings: soc: qcom: spm: Add compatibles for MSM8976 L2

Add SPM AVS Wrapper 2 compatibles for MSM8976's L2 cache.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20221104133452.131227-2-angelogioacchino.delregno@collabora.com