basic: fix for IPv6 status (#4224)

Even if
```
   cat /proc/sys/net/ipv6/conf/all/disable_ipv6
1
```

is disabled

cat /proc/net/sockstat6

```
TCP6: inuse 2
UDP6: inuse 1
UDPLITE6: inuse 0
RAW6: inuse 0
FRAG6: inuse 0 memory 0
 ```

Looking for /proc/net/if_inet6 is the right choice.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/basic/socket-util.c b/src/basic/socket-util.c
index 6093e47172..5c829e0e7e 100644
--- a/src/basic/socket-util.c
+++ b/src/basic/socket-util.c
@@ -441,7 +441,7 @@ const char* socket_address_get_path(const SocketAddress *a) {
 }
 
 bool socket_ipv6_is_supported(void) {
-        if (access("/proc/net/sockstat6", F_OK) != 0)
+        if (access("/proc/net/if_inet6", F_OK) != 0)
                 return false;
 
         return true;