firmware: qcom_scm-64: Add SCM results struct

Remove knowledge of arm_smccc_res struct from client wrappers so that
client wrappers only work QCOM SCM data structures. SCM calls may have
up to 3 arguments, so qcom_scm_call_smccc is responsible now for filling
those 3 arguments accordingly. This is necessary to support merging
legacy and SMC conventions in an upcoming patch.

Tested-by: Brian Masney <masneyb@onstation.org> # arm32
Tested-by: Stephan Gerhold <stephan@gerhold.net>
Signed-off-by: Elliot Berman <eberman@codeaurora.org>
Link: https://lore.kernel.org/r/1578431066-19600-7-git-send-email-eberman@codeaurora.orgSigned-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>