not, depending on the port-specific environment.
Separate panic() and exit() so that the mi/default panic() can be used
without conflicting with a local exit() definition, move exit(void)
prototype to the default exit() implementation.
Closes PR bin/6990 by Wolfgang Helbig <helbig@Informatik.BA-Stuttgart.DE>.
(PR#1404). Things to be noted:
- all IP addresses are now `struct in_addr's.
- the function rarp_getipaddress() no longer return `myip'; in stead
it returns -1 on failure (errno set), 0 on success. `myip' is set
as a size-effect.
