soundwire: slave: use SDW_DISCO_LINK_ID()

use SDW_DISCO_LINK_ID() in slave code to extract field values instead of
open coding masks and shift operations to extract link_id
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Tested-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20200903114504.1202143-4-vkoul@kernel.orgSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/soundwire/slave.c

@@ -106,7 +106,7 @@ static bool find_slave(struct sdw_bus *bus,
 	}
 
 	/* Extract link id from ADR, Bit 51 to 48 (included) */
-	link_id = (addr >> 48) & GENMASK(3, 0);
+	link_id = SDW_DISCO_LINK_ID(addr);
 
 	/* Check for link_id match */
 	if (link_id != bus->link_id)