Firmware API changes which introduced 'num_elems' param in several probe
structs such as sof_ipc_probe_dma_add_params also impacted getter for
both, DMA and probe points. All struct handlers except for
sof_ipc_probe_info_params have been updated. Align said handler too to
calculate payload size correctly.

Fixes: f3b433e4 ("ASoC: SOF: Implement Probe IPC API")
Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200309142124.29262-1-cezary.rojewski@intel.comSigned-off-by: Mark Brown <broonie@kernel.org>