include/linux/libata.h: fix typo

Signed-off-by: NAndrea Gelmini <andrea.gelmini@gelma.net>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

include/linux/libata.h

@@ -342,7 +342,7 @@ enum {
 	ATA_EHI_DID_HARDRESET	= (1 << 17), /* already soft-reset this port */
 	ATA_EHI_PRINTINFO	= (1 << 18), /* print configuration info */
 	ATA_EHI_SETMODE		= (1 << 19), /* configure transfer mode */
-	ATA_EHI_POST_SETMODE	= (1 << 20), /* revaildating after setmode */
+	ATA_EHI_POST_SETMODE	= (1 << 20), /* revalidating after setmode */
 
 	ATA_EHI_DID_RESET	= ATA_EHI_DID_SOFTRESET | ATA_EHI_DID_HARDRESET,