dfu: NAND specific routines for DFU operation

Support for NAND storage devices to work with the DFU framework.

Signed-off-by: Pantelis Antoniou <panto@antoniou-consulting.com>
Signed-off-by: Tom Rini <trini@ti.com>
Acked-by: Scott Wood <scottwood@freescale.com>
diff --git a/README b/README
index 7879eef..276fac9 100644
--- a/README
+++ b/README
@@ -1357,6 +1357,9 @@
 		CONFIG_DFU_MMC
 		This enables support for exposing (e)MMC devices via DFU.
 
+		CONFIG_DFU_NAND
+		This enables support for exposing NAND devices via DFU.
+
 		CONFIG_SYS_DFU_MAX_FILE_SIZE
 		When updating files rather than the raw storage device,
 		we use a static buffer to copy the file into and then write