Kconfig: Add a CONFIG_IDE option

At present IDE support is controlled by CONFIG_CMD_IDE. Add a separate
CONFIG_IDE option so that IDE support can be enabled without requiring
the 'ide' command.

Update existing users and move the ide driver into drivers/block since
it should not be in common/.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/include/configs/sheevaplug.h b/include/configs/sheevaplug.h
index a111057..9d2c106 100644
--- a/include/configs/sheevaplug.h
+++ b/include/configs/sheevaplug.h
@@ -90,13 +90,13 @@
 /*
  * SATA driver configuration
  */
-#ifdef CONFIG_CMD_IDE
+#ifdef CONFIG_IDE
 #define __io
 #define CONFIG_IDE_PREINIT
 #define CONFIG_MVSATA_IDE_USE_PORT0
 #define CONFIG_MVSATA_IDE_USE_PORT1
 #define CONFIG_SYS_ATA_IDE0_OFFSET	MV_SATA_PORT0_OFFSET
 #define CONFIG_SYS_ATA_IDE1_OFFSET	MV_SATA_PORT1_OFFSET
-#endif /* CONFIG_CMD_IDE */
+#endif /* CONFIG_IDE */
 
 #endif /* _CONFIG_SHEEVAPLUG_H */