powerpc/mpc83xx: add support for new SPL

This adds arch support for PPC mpc83xx to boot "minimal" (4K) SPLs
using the new infrastructure.

Existing nand_spl targets are updated to deal with the name change
from nand_init.c to spl_minimal.c (as in theory this isn't limited
to NAND anymore).

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
diff --git a/README b/README
index 5105e64..264a27f 100644
--- a/README
+++ b/README
@@ -2779,6 +2779,12 @@
 		CONFIG_SPL_FAT_LOAD_PAYLOAD_NAME
 		Filename to read to load U-Boot when reading from FAT
 
+		CONFIG_SPL_MPC83XX_WAIT_FOR_NAND
+		Set this for NAND SPL on PPC mpc83xx targets, so that
+		start.S waits for the rest of the SPL to load before
+		continuing (the hardware starts execution after just
+		loading the first page rather than the full 4K).
+
 		CONFIG_SPL_NAND_BASE
 		Include nand_base.c in the SPL.  Requires
 		CONFIG_SPL_NAND_DRIVERS.