sata_sil24: remove unused sil24_port_multiplier

AFAICT, struct sil24_port_multiplier isn't used anywhere. Remove it.
Signed-off-by: NGrant Grundler <grundler@google.com>
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

drivers/ata/sata_sil24.c

@@ -51,13 +51,6 @@ struct sil24_sge {
 	__le32	flags;
 };
 
-/*
- * Port multiplier
- */
-struct sil24_port_multiplier {
-	__le32	diag;
-	__le32	sactive;
-};
 
 enum {
 	SIL24_HOST_BAR		= 0,