firmware: qcom_scm-32: Create common legacy atomic call

Downstream SCM driver legacy atomic calling convention supports up to 5
arguments and 3 return values. Create one function to support this
combination.

Change-Id: I516d920e00d6da99a1f8290c2ed8654c75f268f9
Signed-off-by: Elliot Berman <eberman@codeaurora.org>