lpm-levels: Log cluster_enter event only for non default levels

Only cluster_enter events log for default levels causes
inconsistency. Log them only if the any low power mode is selected.

CRs-fixed: 692014
Change-Id: I5c549c1f9139d67a73e288a0393a19e52e9d2412
Signed-off-by: Archana Sathyakumar <asathyak@codeaurora.org>