libata: functions with definition should not be extern

Noticed by sparse
drivers/ata/libata-core.c:3380:12: warning: function 'ata_wait_after_reset' with external linkage has definition

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

drivers/ata/libata-core.c

@@ -3377,7 +3377,7 @@ int ata_wait_ready(struct ata_link *link, unsigned long deadline,
  *	RETURNS:
  *	0 if @linke is ready before @deadline; otherwise, -errno.
  */
-extern int ata_wait_after_reset(struct ata_link *link, unsigned long deadline,
+int ata_wait_after_reset(struct ata_link *link, unsigned long deadline,
 				int (*check_ready)(struct ata_link *link))
 {
 	msleep(ATA_WAIT_AFTER_RESET_MSECS);