NFC: digital: Fix a memory leak in NFC-F listening mode

When configured as a target listening for a SENSF_REQ poll command, a
nfcid2 array was allocated for no reason leading to a memory leak. The
nfcid2 is sent by the target in the SENSF_RES reply.

Signed-off-by: Thierry Escande <thierry.escande@collabora.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>