Instead of forcing -fnative-struct into CFLAGS when using gcc for Win32,

Instead of forcing -fnative-struct into CFLAGS when using gcc for Win32,

2002-09-29  Tor Lillqvist  <tml@iki.fi>

	* configure.in: Instead of forcing -fnative-struct into CFLAGS
	when using gcc for Win32, check for gcc version 3.x which uses
	-mms-bitfields instead. Also check if either of these switches is
	actually available at all, and warn if not. Thanks to Soren
	Andersen for the inspiration.