interconnect: qcom: Use icc_sync_state

Lowering the bandwidth on the bus might have negative consequences if
it's done before all consumers had a chance to cast their vote. Now by
default the framework sets the bandwidth to maximum during boot. We need
to use the icc_sync_state callback to notify the framework when all
consumers are probed and there is no need to keep the bandwidth set to
maximum anymore.

Link: https://lore.kernel.org/r/20200825170152.6434-4-georgi.djakov@linaro.org
Reviewed-by: Saravana Kannan <saravanak@google.com>
Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>