ide-floppy: Fix unformatted media crash

A ZIP or similar with unformatted media will cause crashes when attempts
are made to read/write it in some cases. This is because bs_factor is
zero and we divide by it causing an oops.

As the size of a non-accessible/non-existant media is really a bit of a
zen question it doesn't matter if non-existant media is 512 bytes per
sector or zero. Setting it to 1 causes us to generate 512 bytes/sector
accesses and error properly.

Based on a fix found lurking in an ancient bugzilla entry since about 2004 (ugghhh)
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>

drivers/ide/ide-floppy.c

@@ -1438,7 +1438,8 @@ static int idefloppy_get_capacity (ide_drive_t *drive)
 	
 	drive->bios_cyl = 0;
 	drive->bios_head = drive->bios_sect = 0;
-	floppy->blocks = floppy->bs_factor = 0;
+	floppy->blocks = 0;
+	floppy->bs_factor = 1;
 	set_capacity(floppy->disk, 0);
 
 	idefloppy_create_read_capacity_cmd(&pc);