libata: add R-Car SATA driver

Add Renesas R-Car on-chip 3Gbps SATA controller driver.

Signed-off-by: Vladimir Barinov <vladimir.barinov@cogentembedded.com>
[Sergei: few bugs fixed, significant cleanup]
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
index 996d16c..9b58d32 100644
--- a/drivers/ata/Kconfig
+++ b/drivers/ata/Kconfig
@@ -260,6 +260,14 @@
 
 	  If unsure, say N.
 
+config SATA_RCAR
+	tristate "Renesas R-Car SATA support"
+	depends on ARCH_SHMOBILE && ARCH_R8A7779
+	help
+	  This option enables support for Renesas R-Car Serial ATA.
+
+	  If unsure, say N.
+
 config SATA_SIL
 	tristate "Silicon Image SATA support"
 	depends on PCI