scsi: Move drivers into new drivers/scsi directory

At present we have the SCSI drivers in the drivers/block and common/
directories. It is better to split them out into their own place. Use
drivers/scsi which is what Linux does.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig
new file mode 100644
index 0000000..db1606e
--- /dev/null
+++ b/drivers/scsi/Kconfig
@@ -0,0 +1,17 @@
+config SCSI
+	bool "Support SCSI controllers"
+	help
+	  This enables support for SCSI (Small Computer System Interface),
+	  a parallel interface widely used with storage peripherals such as
+	  hard drives and optical drives. The SCSI standards define physical
+	  interfaces as well as protocols for controlling devices and
+	  tranferring data.
+
+config DM_SCSI
+	bool "Support SCSI controllers with driver model"
+	depends on BLK
+	help
+	  This option enables the SCSI (Small Computer System Interface) uclass
+	  which supports SCSI and SATA HDDs. For every device configuration
+	  (IDs/LUNs) a block device is created with RAW read/write and
+	  filesystem support.