Fix activation of power limit.
Fix activation of power limit.

As of now in energyscale tests, we are trying to activate power limit without setting
proper limit. So if some platforms before hand has no limit set, then activation will fail.
activation will work if platform has already set to a particular power limit.

ipmitool -H <bmc-ip> -I lanplus -U ADMIN -P admin  dcmi power get_limit

    Current Limit State: No Active Power Limit  <-------Here we can see there is no active power limit
    Exception actions:   Log Event to SEL
    Power Limit:         0 Watts
    Correction time:     1000 milliseconds
    Sampling period:     10 seconds

ipmitool -H <bmc-ip> -I lanplus -U ADMIN -P admin dcmi power activate
Power limit activation failed

To avoid this failure, this patch removes the activate power limit.

get_limit--->set_limit---->activate

So above is the right order to set and activate

Signed-off-by: Pridhiviraj Paidipeddi <fd8ea14509c256cbd04eaa4ee745a213945e70a1@linux.vnet.ibm.com>

open-power/op-test-framework,open-power/op-test-framework,open-power/op-test-framework