dpll: fix broken error path in dpll_pin_alloc(..)

If pin type is not expected, or pin properities failed to allocate
memory, the unwind error path shall not destroy pin's xarrays, which
were not yet initialized.
Add new goto label and use it to fix broken error path.

Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>