ASoC: Intel: Skylake: Fix missing sentinel in sst_acpi_mach

To make it consistent, add sentinel for sst_cnl_devdata also.
Signed-off-by: Guneshwor Singh <guneshwor.o.singh@intel.com>
Acked-By: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/intel/skylake/skl.c

@@ -1011,6 +1011,7 @@ static const struct sst_acpi_mach sst_cnl_devdata[] = {
 		.fw_filename = "intel/dsp_fw_cnl.bin",
 		.pdata = &cnl_pdata,
 	},
+	{}
 };
 
 /* PCI IDs */