OneNAND: Add simple OneNAND SPL

This introduces small OneNAND loader, fitting into 1kB of space (smallest
possible OneNAND RAM size). Some devices equipped with such crappy chips will
use this.

Signed-off-by: Marek Vasut <marek.vasut@gmail.com>
Cc: Albert ARIBAUD <albert.u.boot@aribaud.net>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Scott Wood <scottwood@freescale.com>

V2: Introduce spl_onenand_load_image() to load data from OneNAND in SPL
V3: Cleanup, align with nand_spl. Skip whole blocks.
diff --git a/drivers/mtd/onenand/Makefile b/drivers/mtd/onenand/Makefile
index b984bd4..b090d40 100644
--- a/drivers/mtd/onenand/Makefile
+++ b/drivers/mtd/onenand/Makefile
@@ -25,8 +25,12 @@
 
 LIB	:= $(obj)libonenand.o
 
+ifndef	CONFIG_SPL_BUILD
 COBJS-$(CONFIG_CMD_ONENAND)	:= onenand_uboot.o onenand_base.o onenand_bbt.o
 COBJS-$(CONFIG_SAMSUNG_ONENAND)	+= samsung.o
+else
+COBJS-y				:= onenand_spl.o
+endif
 
 COBJS	:= $(COBJS-y)
 SRCS	:= $(COBJS:.o=.c)