Linux driver to expose rpmsg/open-amp endpoints to usr space via TTY interface and a "clear" channel.

The current implmentation is for the Udoo Neo (http://www.udoo.org/udoo-neo/)
Linux on A9 (rpmsg) <-----> (rpmsg) M4 using FreeRTOS

The goal is to have one general Linux driver to support (1) Channel and (2) endpoints

• endpt 127 is for usr space (Working)
• endpt 126 is for tty usr space (Working )
• endpt 125 is for Ethernet driver. Linux (Ethernet) (rpmsg) <-----> rpmsg LwIP/FreeRTOS (TCP) on FreeRTOS (M4)

usr-neoproxy.c is a test program to send, validate and provide bandwidth information. Uses libev (http://software.schmorp.de/pkg/libev.html) library to manage epoll