msm: pm-8x60: Increase warn timeout for sleep sts check

Arm cores take longer time to enter sleep. Wait for longer
time before warning until the CPU goes to sleep state.

Change-Id: I15caa8b2b2560aa68a4f4967c3364533234584b7
Signed-off-by: Priyanka Mathur <pmathur@codeaurora.org>