* fhandler.h (class fhandler_dev_raw): Remove is_writing flag.

	* fhandler.h (class fhandler_dev_raw): Remove is_writing flag.
	Remove declaration of writebuf.
	(class fhandler_dev_floppy): Remove declaration of close.
	* fhandler_floppy.cc (fhandler_dev_floppy::close): Delete.
	(fhandler_dev_floppy::lseek): Remove calls to writebuf.  Set
	eom_detected to false after successful seek.
	* fhandler_raw.cc (fhandler_dev_raw::writebuf): Delete.
	(fhandler_dev_raw::raw_read): Remove calls to writebuf.
	(fhandler_dev_raw::raw_write): Always invalidate buffer.