[PATCH rtems-lwip] README: Add build instruction

[Kinsey Moore]

On 7/21/2022 14:16, Vijay Kumar Banerjee wrote:
> ---
>   README | 18 ++++++++++++++++++
>   1 file changed, 18 insertions(+)
>
> diff --git a/README b/README
> index 91e42ae..99800bf 100644
> --- a/README
> +++ b/README
> @@ -12,3 +12,21 @@ The sources presented here originate in one of several locations described by
>   the ORIGIN.* files and whose license is described by the COPYING.* files.
>   Commits adding such files should include the hash of the target repository if
>   applicable.
> +
> +Installation Instructions
> +-------------------------
> +1. Populate the git submodules:
> +
> +```
> +git submodule init
> +git submodule update
> +```
> +2. Configure and build
> +```
> +./waf configure --prefix=INSTALL_PREFIX
Can this be run without specifying which BSPs it's being configured for? 
I've only ever configured it with an explicit list.
> +./waf
> +./waf install
> +```
> +
> +More `waf` arguments can be found by using:
> +`./waf --help`