NET: Rename uiphdr_ipaddr_copy to net_ipaddr_hdrcopy, uip_ip4addr_conv to net_ip4addr_conv32, and uip_ethaddr_cmp to eth_addr_cmp

Rename static functions from uip_* to something more appropriate.  Globally scoped functions will take more work

SAMA5D4-EK: NSH confuration now has FAT/ROMFS, /dev/zero, /dev/random via TRNG, an NSH startup script, and a RAM disk at /tmp