soc: qcom: rpm-smd: Suppress driver bind/unbind feature

RPM-SMD driver do not support bind/unbind using sysfs.
Set suppress bind attribute to disallow this.

Change-Id: Ib1eab4af4d40eeaa1deac87c3eff85ecf5649ee1
Signed-off-by: Maulik Shah <mkshah@codeaurora.org>