ASoC: SDCA: Allow read-only controls to be deferrable

The current SDCA Control parsing only checks the deferrable flag for
Read/Write and Dual Ranked controls. However, reads can defer as well as
writes so Read Only controls should also check for the deferrable flag.
Add the handling for this into find_sdca_entity_control().

Fixes: 42b144c ("ASoC: SDCA: Add SDCA Control parsing")
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.dev>
Link: https://patch.msgid.link/20250707124155.2596744-2-ckeepax@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: charleskeepax

sound/soc/sdca/sdca_functions.c

@@ -881,7 +881,8 @@ static int find_sdca_entity_control(struct device *dev, struct sdca_entity *enti
 			control->value = tmp;
 			control->has_fixed = true;
 		}
-
+		fallthrough;
+	case SDCA_ACCESS_MODE_RO:
 		control->deferrable = fwnode_property_read_bool(control_node,
 								"mipi-sdca-control-deferrable");
 		break;