cpuidle: lpm-levels: Remove local_irq_enable from lpm_cpuidle_select

Remove enabling of interrupts in lpm_cpuidle_select in case of
no low power mode selected as it is taken care in cpuidle_idle_call.

Change-Id: Id9fabe6116908b4c64bd6659d02252684db10958
Signed-off-by: Srinivas Rao L <lsrao@codeaurora.org>