ARM: dts: msm: enable simple led flash controlled by gpio for QRD SKUAB

This is a low cost led which is driven by system power, and use a
transistor controlled by pmic gpio 1 to gate its on/off state. This
is also a single mode flash led with no difference between flash
mode and torch mode. Enable this led in device tree.

CRs-fixed: 561538
Change-Id: I72a188d4dafbf600090861e77a84dac84f33e7b3
Signed-off-by: Xu Kai <kaixu@codeaurora.org>