Beagle board uboot compilation

• 先在 /opt/toolchains 底下安裝 linaro 的 toolchain
• uboot source code 中, edit Makefile, 修改底下的 CROSS_COMPILE 變數,反映實際toolchain路徑

ifeq ($(ARCH),arm)
CROSS_COMPILE = /opt/toolchains/gcc-linaro-arm-linux-gnueabihf-4.8-2013.07-1_linux/bin/arm-linux-gnueabihf-

• make ARCH=arm omap3_beagle_config

• make ARCH=arm all -j 8