Since commit acb2505d01 ("openrisc: fix copy_from_user()"),
copy_from_user() returns the number of bytes requested, not the
number of bytes not copied.
Cc: Al Viro <viro@zeniv.linux.org.uk>
Fixes: acb2505d01 ("openrisc: fix copy_from_user()")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>