firmware: qcom_scm-64: Add atomic version of qcom_scm_call

There are scnenarios where drivers are required to make a
scm call in atomic context, such as in one of the qcom's
arm-smmu-500 errata [1].

[1] ("https://source.codeaurora.org/quic/la/kernel/msm-4.9/commit/


      drivers/iommu/arm-smmu.c?h=CogSystems-msm-49/
      msm-4.9&id=da765c6c75266b38191b38ef086274943f353ea7")

Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Ondrej Kubik <ondrej.kubik@canonical.com>