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

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.