cygwin configure fails with thread-safety

For cygwin builds, src/test/thread/thread_test.c needs to include
sys/param.h to get MAXHOSTNAMELEN.  configure is currently failing when
--enable-thread-safety is used because of this.  See attached patch
against head.

--
Andrew Chernow
eSilo, LLC
every bit counts
http://www.esilo.com/
Index: src/test/thread/thread_test.c
===================================================================
RCS file: /projects/cvsroot/pgsql/src/test/thread/thread_test.c,v
retrieving revision 1.5
diff -C6 -r1.5 thread_test.c
*** src/test/thread/thread_test.c    1 Jan 2008 19:46:01 -0000    1.5
--- src/test/thread/thread_test.c    17 Nov 2008 14:59:56 -0000
***************
*** 44,55 ****
--- 44,59 ----
  #include <sys/types.h>
  #include <pwd.h>
  #include <string.h>
  #include <fcntl.h>
  #include <errno.h>

+ /* CYGWIN requires this for MAXHOSTNAMELEN */
+ #ifdef __CYGWIN__
+ #include <sys/param.h>
+ #endif

  /******************************************************************
   * Windows Hacks
   *****************************************************************/

  #ifdef WIN32