Build ARM Cross Compiler (arm-linux)

Main Packages:
1. linux kernel headers
2. binutils
3. gcc
4. glibc
5. glibc-ports

Problems:

1. glibc-2.11 needs cpuid.h
2. glibc-2.10.1 only supports as,ld version 2.13-2.19: apply the patch
   
3. --with-sysroot will cause the problem
4. glibc: cannot find -lgcc_eh, modify Makeconfig.

Reference
[1] clfs-sysroot, http://cross-lfs.org/view/clfs-sysroot/