hwmon: (fam15h_power) Increase output resolution

hwmon: (fam15h_power) Increase output resolution

On high CPU load the accumulating values in the running_avg_cap
register are very low (below 10), so averaging them too early leads
to unnecessary poor output resolution. Since we pretend to output
micro-Watt we better keep all the bits we have as long as possible.

Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: Guenter Roeck <guenter.roeck@ericsson.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
(cherry picked from commit 941a956b0e387b21f385f486c34ef67576775cfc)

Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>