[PATCH] libata: flush COMRESET set and clear

Updated patch to fix erroneous flush of COMRESET set and missing flush
of COMRESET clear.  Created a new routine scr_write_flush() to try to
prevent this in the future.  Also, this patch is based on libata-2.6
instead of the previous libata-dev-2.6 based patch.

Signed-off-by: Brett Russ <russb@emc.com>

Index: libata-2.6/drivers/scsi/libata-core.c
===================================================================
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 505160a..1f7e203 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -584,6 +584,13 @@
 	ap->ops->scr_write(ap, reg, val);
 }
 
+static inline void scr_write_flush(struct ata_port *ap, unsigned int reg, 
+				   u32 val)
+{
+	ap->ops->scr_write(ap, reg, val);
+	(void) ap->ops->scr_read(ap, reg);
+}
+
 static inline unsigned int sata_dev_present(struct ata_port *ap)
 {
 	return ((scr_read(ap, SCR_STATUS) & 0xf) == 0x3) ? 1 : 0;