qseecom: Add ARMv8 SMC interface support

The scm library has added support for a new secure world
interface that is more aligned to the ARMv8 SMC calling
convention. Make changes to support new ARMv8 SMC interface
while maintaining backward compatibility.

Change-Id: I41d03cf0e6ef3ce183ad6bdf22b7881b4dc583ee
Signed-off-by: Zhen Kong <zkong@codeaurora.org>