Segfault: smb2_free_pdu

Immediate KO on anonymous login to Windows 10 21H2 shares. Regression from previous build.

0   libsystem_kernel.dylib        	0x00000001bdeb8b78 __pthread_kill + 8
1   libsystem_pthread.dylib       	0x00000001f74d43bc pthread_kill + 268 (pthread.c:1668)
2   libsystem_c.dylib             	0x000000019162c51c abort + 168 (abort.c:118)
3   libsystem_malloc.dylib        	0x0000000198768a04 malloc_vreport + 552 (malloc_printf.c:183)
4   libsystem_malloc.dylib        	0x0000000198768bdc malloc_report + 64 (malloc_printf.c:192)
5   libsystem_malloc.dylib        	0x000000019874de38 free + 300 (malloc.c:1963)
6   MobileVLCKit                  	0x000000010554faa0 smb2_free_pdu + 72 (pdu.c:194)
7   MobileVLCKit                  	0x0000000105556210 smb2_read_data + 1368 (socket.c:587)
8   MobileVLCKit                  	0x000000010555677c smb2_read_from_socket + 84 (socket.c:630)
9   MobileVLCKit                  	0x000000010555677c smb2_service_fd + 740 (socket.c:791)
10  MobileVLCKit                  	0x000000010647f75c vlc_smb2_mainloop + 336 (smb2.c:232)
11  MobileVLCKit                  	0x000000010647e948 vlc_smb2_connect_open_share + 392 (smb2.c:682)
12  libsystem_pthread.dylib       	0x00000001f74cde68 thread_start + 8