ARM: dts: msm: Set default status of I2C_8 as disabled

Set default configuration of I2C_8 instance to disabled
state, for MSM8996 vplatform, such that clients can overwrite
and enable respective instance as per need.

Change-Id: I2e873cb27ba028323d6dc1a0aa302f2c32e2b69f
Signed-off-by: Shrey Vijay <shreyv@codeaurora.org>