m68k: mcf5445x: move early ddr init as board-specific

For certain boot types and sbf, for V4 cpu's, an early ddr/sdram init
is required. This patch moves this ddr/sdram early initalization
away from start.S (to be board related).

Signed-off-by: Angelo Dureghello <angelo@sysam.it>
diff --git a/board/freescale/m54418twr/Makefile b/board/freescale/m54418twr/Makefile
index 371c04a..4ef1e5a 100644
--- a/board/freescale/m54418twr/Makefile
+++ b/board/freescale/m54418twr/Makefile
@@ -5,3 +5,5 @@
 #
 
 obj-y	= m54418twr.o
+extra-y	+= sbf_dram_init.o
+