coreutils: add uname patch

On linux platforms, grok /proc/cpuinfo for the CPU/vendor info.

Signed-off-by: Martin Banky <Martin.Banky@gmail.com>
Acked-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>