ARC port to uClibc

For this port, I would like to give due credit to:

- Folks from Codito technologies (Sameer, Amit, Kanika, Ramana,...)
   who did the very first port

- ARC UK from 2007-2009 (Joern, Irfan, Khurram, Phil...

- Late Brendan Kehoe (may he RIP)

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
ARC defconfigs

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>