floppy: don't write kernel-only members to FDRAWCMD ioctl output

Do not leak kernel-only floppy_raw_cmd structure members to userspace.
This includes the linked-list pointer and the pointer to the allocated
DMA space.

Signed-off-by: Matthew Daley <mattd@bugfuzz.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
static void reset_interrupt(void)
{
	debugt(__func__, "");
	result();		/* get the status ready for set_fdc */
	if (FDCS->reset) {
		pr_info("reset set in interrupt, calling %pf\n", cont->error);
		cont->error();	/* a reset just after a reset. BAD! */
	}
	cont->redo();
}

static void reset_interrupt(void)
{
	debugt(__func__, "");
	result();		/* get the status ready for set_fdc */
	if (FDCS->reset) {
		pr_info("reset set in interrupt, calling %pf\n", cont->error);
		cont->error();	/* a reset just after a reset. BAD! */
	}
	cont->redo();
}
