zynqmp: pm_service: use zynqmp_ipi APIs

Use zynqmp_ipi APIs to access IPI registers in pm_service.
As the zynqmp_ipi APIs doesn't cover IPI buffers, the pm_ipi
in pm_service will still directly access the IPI buffers.

Signed-off-by: Wendy Liang <jliang@xilinx.com>
5 files changed