README issue

[quangdaovu]

The first part of README is:

Getting the sources

This repository uses submodules. You need the --recursive option to fetch the submodules automatically

$ git clone --recursive https://github.com/riscv/riscv-gnu-toolchain

Alternatively :

$ git clone https://github.com/riscv/riscv-gnu-toolchain
$ cd riscv-gnu-toolchain
$ git submodule update --init --recursive

Should we change https://github.com/riscv/riscv-gnu-toolchain to https://github.com/pulp-platform/pulp-riscv-gnu-toolchain?

[haugoug]

Yes indeed this is better I will update it