ptp: Fix resource leak in case of error

A call to 'ida_simple_remove()' is missing in the error handling path.

This as been spotted with the following coccinelle script which tries to
detect missing 'ida_simple_remove()' call in error handling paths.

///////////////
@@
expression x;
identifier l;
@@

*   x = ida_simple_get(...);
    ...
    if (...) {
    ...
    }
    ...
    if (...) {
       ...
       goto l;
    }
    ...
*   l: ... when != ida_simple_remove(...);
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/ptp/ptp_clock.c

@@ -263,6 +263,7 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
 no_device:
 	mutex_destroy(&ptp->tsevq_mux);
 	mutex_destroy(&ptp->pincfg_mux);
+	ida_simple_remove(&ptp_clocks_map, index);
 no_slot:
 	kfree(ptp);
 no_memory: