ARM: dts: msm: modify apds9930 light sensor gain in device tree

Modify apds9930 light sensor gain, so the lux value can normal
for the low light environment

Change-Id: I26f92b8530d6a575e36858827d10b62c4831fc36
CRs-Fixed: 703157
Signed-off-by: Daqing Chen <chendaqing@codeaurora.org>