[Xastir] New configure.ac script

[Steve Dimse]

More errors, even after I fixed the config script:

interface.c: In function `port_read':
interface.c:2223: `socklen_t' undeclared (first use in this function)
interface.c:2223: (Each undeclared identifier is reported only once
interface.c:2223: for each function it appears in.)
interface.c:2223: parse error before "from_len"
interface.c:2270: `from_len' undeclared (first use in this function)
interface.c:2270: parse error before "sizeof"

Any idea where this came from? The last CVS download I did, perhaps a week ago,
compiled fine...

Steve K4HG