This patch is in use by Cygwin for years, upstream to GCC.

	* gcc/config/i386/mingw.opt (fset-stack-executable): Removed.
	* gcc/config/i386/cygming.opt (fset-stack-executable): Moved
	from mingw.opt.
	* gcc/config/i386/cygwin.h: Define CHECK_EXECUTE_STACK_ENABLED.
	* ligcc/config.host (*-cygwin): Include file from mingw
	config/i386/enable-execute-stack-mingw32.c

From-SVN: r250914