acpi_power_meter: use the same struct {rw,ro}_sensor_template for both

We don't need both, when we can just key the read/write off of the
presence of the .set member.

Signed-off-by: Kyle McMartin <kyle@redhat.com>
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>

diff --cc drivers/hwmon/acpi_power_meter.c
Simple merge