ata: libata-core: replace "its" with "it is"

and "isn't" with "is not". The former fixes the typo while the latter
just uses the same formal language.
Signed-off-by: Diego Viola <diego.viola@gmail.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>

drivers/ata/libata-core.c

@@ -1398,7 +1398,7 @@ unsigned long ata_id_xfermask(const u16 *id)
 
 		/* But wait.. there's more. Design your standards by
 		 * committee and you too can get a free iordy field to
-		 * process. However its the speeds not the modes that
+		 * process. However it is the speeds not the modes that
 		 * are supported... Note drivers using the timing API
 		 * will get this right anyway
 		 */
@@ -5559,7 +5559,7 @@ static void ata_finalize_port_ops(struct ata_port_operations *ops)
  *	Start and then freeze ports of @host.  Started status is
  *	recorded in host->flags, so this function can be called
  *	multiple times.  Ports are guaranteed to get started only
- *	once.  If host->ops isn't initialized yet, its set to the
+ *	once.  If host->ops is not initialized yet, it is set to the
  *	first non-dummy port ops.
  *
  *	LOCKING: