ARM: dts: msm: add sync write delay of WLED for MSM8917/53

Add DT property for sync write delay for WLED module, which is needed
between two consecutive sync register writes, for MSM8917/53 MTP and
CDP that use PMI8937.

CRs-Fixed: 993090
Change-Id: Ic3ad381ff8176a1f1aa1578e1233ba19240fe1b4
Signed-off-by: Shantanu Jain <shjain@codeaurora.org>