Add support for generic EEPROM access via a character driver.  Add also the EEPROM driver itself.  From Sebastien Lorquet

Nucleo F4x1RE: Typos in previously untested code. message() does not exist, return value from void function, missing inclusion of errno.h.  From Sébastien Lorquet

Add logic to netdev_findbyaddr() to return the correct network device for the case where a broadcast address is used.  This change caused trivial ripples through other files because additional parameters are required for netdev_findbyaddr() when CONFIG_NET_MULTINIC

Network routing:  Refuse to perform routing table lookups for the Broadcast IP address.  From Brennan Ashton

Extensions to ECP conneciton structure for the case of multiple networks.  See additional comments regarding the similar change for UDP