input: synaptics_i2c_rmi4: Properly enter low power mode

When entering low power mode, i2c pull up regulator
must be set with LPM current, not active current.

This patch is propagated from msm-3.4 kernel.
(commit: cd38a573fd5298101358a00f4f7d4e17ddec8f44
input: synaptics_i2c_rmi4: Properly enter low power mode)

Change-Id: Idc87cd57b8a4f75b665d3045123176b158b16691
Signed-off-by: Amy Maloche <amaloche@codeaurora.org>