drivers/usb/serial/opticon.c: Release resources on kmalloc failure

Several resources have been allocated before this kmalloc failure, and thus
they should be released in this error handling code, as done in nearby
error handling code.

The semantic match that finds this problem is:
(http://coccinelle.lip6.fr/)

// <smpl>
@r exists@
local idexpression urb;
statement S;
position p1,p2;
@@

urb = usb_alloc_urb@p1(...);
... when != urb
if (urb == NULL) S
... when != urb
(
return <+...urb...+>;
|
return@p2 ...;
)

@script:python@
p1 << r.p1;
p2 << r.p2;
@@

cocci.print_main("",p1)
cocci.print_secs("",p2)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>