Fiddle with hard-coded neon config.h to support USE_NONBLOCKING_CONNECT

...see the condition in neon's src/neon_socket.c under which
USE_NONBLOCKING_CONNECT would be enabled.  This should not have any immediate
effect in LibreOffice, as we do not call ne_set_connect_timeout.  But it might
be beneficial to selectively do so in light of rhbz#915743 "thread
deadlock/slow join in insert->hyperlink in impress," to work around neon's
disability to abort potentially blocking calls.

The enabled features are hopefully POSIX-y enough to allow for plain #ifdef UNX.
If not, we need to adapt this to more fine grained conditions.

Change-Id: I6bf0a89c1ae73d7183f515e780fff7fe0ae2fed0
Reviewed-on: https://gerrit.libreoffice.org/2492Tested-by: LibreOffice gerrit bot <gerrit@libreoffice.org>
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>
Tested-by: Stephan Bergmann <sbergman@redhat.com>

neon/configs/config.h

@@ -53,10 +53,14 @@
 /* #undef HAVE_EXPAT */
 
 /* Define to 1 if you have the `fcntl' function. */
-/* #undef HAVE_FCNTL */
+#ifdef UNX
+#define HAVE_FCNTL 1
+#endif
 
 /* Define to 1 if you have the <fcntl.h> header file. */
-/* #undef HAVE_FCNTL_H */
+#ifdef UNX
+#define HAVE_FCNTL_H 1
+#endif
 
 /* Define to 1 if you have the `fstat64' function. */
 #define HAVE_FSTAT64
@@ -71,7 +75,9 @@
 /* #undef HAVE_GETNAMEINFO */
 
 /* Define to 1 if you have the `getsockopt' function. */
-/* #undef HAVE_GETSOCKOPT */
+#ifdef UNX
+#define HAVE_GETSOCKOPT 1
+#endif
 
 /* Define if GnuTLS support is enabled */
 /* #undef HAVE_GNUTLS */
@@ -234,7 +240,9 @@
 #endif
 
 /* Define to 1 if the system has the type `socklen_t'. */
-/* #undef HAVE_SOCKLEN_T */
+#ifdef UNX
+#define HAVE_SOCKLEN_T 1
+#endif
 
 /* Define to 1 if you have the `SSL_SESSION_cmp' function. */
 /* #undef HAVE_SSL_SESSION_CMP */