soc: qcom: icc-bwmon: Fix MSM8998 count unit

MSM8998's BWMON counts in megabytes. Fix it.

Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230531-topic-msm8998-bwmon-v1-1-454f9d550ee5@linaro.org