Fix various typos of valid in comments

Fix various typos of valid.

Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/include/linux/libata.h b/include/linux/libata.h
index f010f18..9eee84b 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -340,7 +340,7 @@
 	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,