ARM: dts: 8916: Add 1400us delay to allow buck decay time.

Add delay of 1400us to allow buck decay to min voltage, this also
adds increase in timeoverhead numbers for L2pc.
Increase the saw2_cfg to add more delay between commands.
Remove the L2pc-norpm as it has no power savings.

Change-Id: I81f45e0c7c20ce8a4398d943330e4af5e506eed4
Signed-off-by: Anji Jonnala <anjir@codeaurora.org>