include/device/dram: Add SPD lengths for DDR3 to DDR5

DDR2 already had a define to specify the SPD length, but other memory
types did not. This led to the value being coded into other locations.
Unify the definition for DDR2 to DDR5 and put the value at the top of
the respective header file.

Signed-off-by: Martin Roth <gaumless@gmail.com>
Change-Id: Id13b9c5d311984d4a98b831a8746d1659724aa96
Reviewed-on: https://review.coreboot.org/c/coreboot/+/78601
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Keith Hui <buurin@gmail.com>
Reviewed-by: Felix Singer <service+coreboot-gerrit@felixsinger.de>
diff --git a/src/include/device/dram/ddr3.h b/src/include/device/dram/ddr3.h
index 8886e64..6efe049 100644
--- a/src/include/device/dram/ddr3.h
+++ b/src/include/device/dram/ddr3.h
@@ -19,6 +19,9 @@
 #include <device/dram/common.h>
 #include <types.h>
 
+/** Maximum SPD size supported */
+#define SPD_SIZE_MAX_DDR3	256
+
 /**
  * Convenience definitions for SPD offsets
  *