Revert "power_state: get rid of write-only variable in SATA"

This reverts commit 559bbe6cbd0d8c68d40076a5f7dc98e3bf5864b2.

Michael S. Tsirkin reports that this changes breaks suspend/resume.

Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index b57fad3..4fbcce7 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -6567,6 +6567,8 @@
 	ata_lpm_enable(host);
 
 	rc = ata_host_request_pm(host, mesg, 0, ATA_EHI_QUIET, 1);
+	if (rc == 0)
+		host->dev->power.power_state = mesg;
 	return rc;
 }
 
@@ -6585,6 +6587,7 @@
 {
 	ata_host_request_pm(host, PMSG_ON, ATA_EH_SOFTRESET,
 			    ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET, 0);
+	host->dev->power.power_state = PMSG_ON;
 
 	/* reenable link pm */
 	ata_lpm_disable(host);