regulator: cpr3-regulator: fix max_aggregated_params debugfs directory

Currently, the max_aggregated_params directory exposed for each
thread reports the aggregated ceiling, floor, open-loop, and last
known closed-loop voltages corresponding to the CPR controller that
the thread is associated with. This is undesirable, since the
max_aggregated_params directory should provide aggregated data for
the multiple regulators associated with the thread.

Change-Id: I5f8577c12badb85ba34b616912d930800197e05e
Signed-off-by: Osvaldo Banuelos <osvaldob@codeaurora.org>