tests/inet_socket: properly detect IPSEC support

Check if XFRM itself is supported by the kernel when deciding whether to
run the IPSEC tests, so that the testsuite can be run on kernels with
CONFIG_XFRM_USER unset, too.

Signed-off-by: Ondrej Mosnacek <[email protected]>
Acked-by: Stephen Smalley <[email protected]>

Author: WOnder93

tests/inet_socket/test

@@ -25,7 +25,9 @@ BEGIN {
     }
 
     $test_ipsec = 0;
-    if ( system("ip xfrm policy help 2>&1 | grep -q ctx") eq 0 ) {
+    if (    system("ip xfrm policy help 2>&1 | grep -q ctx") eq 0
+        and system("ip xfrm policy list &>/dev/null") eq 0 )
+    {
         $test_count += 4;
         $test_ipsec = 1;
     }