ide: endian annotations in ide-floppy.c

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Borislav Petkov <petkovbb@googlemail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>