ipc: rpmsg_service: Convert to devicetree APIs

* Convert device_get_binding to DEVICE_DT_GET
* Convert Kconfig RPMSG_SERVICE_SHM_BASE_ADDRESS and
  RPMSG_SERVICE_SHM_SIZE to DT_REG_ADDR/DT_REG_SIZE

Signed-off-by: Kumar Gala <galak@kernel.org>
3 files changed