[U-Boot] RR v3 PATCH: SMDK6400 Fix some build bug

[seedshope]

Change from V1:
patch 1: 
patch 2: Delete some compile information from commit.
patch 3: Add LED modify information and Delete some compile information from commit.
patch 4: Add new patch for SDRAM init.

Change frome v2:
patch2: Modify Makefile for arch/arm/cpu/arm1176/s3c64xx/cpu_init.s in build error.
It will generat redefine information for "mem_ctrl_asm_init" before the Modify.
patch4: Modify the Sergei Shtylyov comments and change the SDRAM size variable
for PHYS_SDRAM_SIZE_1.

I apply this patch and build ok.