ARM: dts: msm: Add WDI2 offload support over gsi for SM6150

Added device configuration to support WDI2 offload support
over GSI on SM6150 target.

Change-Id: I18c400164a532f3de376b28bd30547deac80c484
Acked-by: Ashok Vuyyuru <avuyyuru@qti.qualcomm.com>
Signed-off-by: Mohammed Javid <mjavid@codeaurora.org>