CVE-2021-47442

In the Linux kernel, the following vulnerability has been resolved: NFC: digital: fix possible memory leak in digital_in_send_sdd_req() 'skb' is allocated in digital_in_send_sdd_req(), but not free when digital_in_send_cmd() failed, which will cause memory leak. Fix it by freeing 'skb' if digital_in_send_cmd() return failed.