NFC: st21nfca: Fix memory leak in device probe and remove

In the Linux kernel, the following vulnerability has been resolved:

NFC: st21nfca: Fix memory leak in device probe and remove

'phy->pending_skb' is alloced when device probe, but forgot to free

in the error handling path and remove path, this cause memory leak

as follows:

unreferenced object 0xffff88800bc06800 (size 512):

comm "8", pid 11775, jiffies 4295159829 (age 9.032s)

hex dump (first 32 bytes):

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................

backtrace:

[<00000000d66c09ce>] __kmalloc_node_track_caller+0x1ed/0x450

[<00000000c93382b3>] kmalloc_reserve+0x37/0xd0

[<000000005fea522c>] __alloc_skb+0x124/0x380

[<0000000019f29f9a>] st21nfca_hci_i2c_probe+0x170/0x8f2

Fix it by freeing 'pending_skb' in error and remove.