Remove erroneous or extra spd.h #includers.

Many of the spd.h #includers don't need it,
and wanted to have spd_sdram() declared instead.
Since they didn't get that, some also had open
coded extern declarations of it instead or as well.
Fix it all up by using spd_sdram.h where needed.

Signed-off-by: Jon Loeliger <jdl@freescale.com>
diff --git a/board/freescale/mpc8555cds/mpc8555cds.c b/board/freescale/mpc8555cds/mpc8555cds.c
index 74c220d..8acbba4 100644
--- a/board/freescale/mpc8555cds/mpc8555cds.c
+++ b/board/freescale/mpc8555cds/mpc8555cds.c
@@ -25,7 +25,7 @@
 #include <asm/processor.h>
 #include <asm/immap_85xx.h>
 #include <ioports.h>
-#include <spd.h>
+#include <spd_sdram.h>
 #include <libfdt.h>
 #include <fdt_support.h>
 
@@ -37,8 +37,6 @@
 extern void ddr_enable_ecc(unsigned int dram_size);
 #endif
 
-extern long int spd_sdram(void);
-
 void local_bus_init(void);
 void sdram_init(void);