block: floppy: Fix uninitialized use of outparam

Fix Smatch-detected error:
drivers/block/floppy.c:3569 fd_locked_ioctl() error:
uninitialized symbol 'outparam'.

Smatch may incorrectly warn about uninitialized use of 'outparam'
in fd_locked_ioctl(), even though all _IOC_READ commands guarantee
its initialization. Initialize outparam to NULL to make this explicit
and suppress the false positive.

Signed-off-by: Purva Yeshi <[e-mail]>
Reviewed-by: Denis Efremov <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Jens Axboe <[e-mail]>

drivers/block/floppy.c

···
 		struct floppy_max_errors max_errors;
 		struct floppy_drive_params dp;
 	} inparam;		/* parameters coming from user space */
-	const void *outparam;	/* parameters passed back to user space */
+	const void *outparam = NULL;	/* parameters passed back to user space */
 
 	/* convert compatibility eject ioctls into floppy eject ioctl.
 	 * We do this in order to provide a means to eject floppy disks before