ARM: dts: msm: add latency before de-assert PERST for PCIe

nodes in MSM8994

The endpoints of RC0 and RC1 both require 10ms latency between
PCIe power on and de-assert PERST. Thus, add latency to
PCIe0 and PCIe1 for MSM8994.

Change-Id: I0fc9d60791bc01fa1da45ffb4e6c6520cecce878
Signed-off-by: Tony Truong <truong@codeaurora.org>