configure.in: Check for in_addr_t in netinet/in.h too.

configure.in: Check for in_addr_t in netinet/in.h too.

* configure.in: Check for in_addr_t in netinet/in.h too.  Check
for ip_mreq too.
* acconfig.h: Define HAVE_IN_ADDR_T instead of in_addr_t.
(HAVE_STRUCT_IP_MREQ): Added.
* configure, include/config.h.in: Rebuilt.
* java/net/natInetAddress.cc (aton): Typedef in_addr_t to jint
if needed.
* java/net/natPlainDatagramSocketImpl.cc (McastReq, mcastGrp):
Disable if ip_mreq is not available.

From-SVN: r28798