libxtables: prefix/order - move check_inverse to xtables.c

This also adds a warning that intrapositional negation support
is deprecated.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
diff --git a/extensions/libipt_LOG.c b/extensions/libipt_LOG.c
index 23790a0..bc7e8a4 100644
--- a/extensions/libipt_LOG.c
+++ b/extensions/libipt_LOG.c
@@ -112,7 +112,7 @@
 			exit_error(PARAMETER_PROBLEM,
 				   "Can't specify --log-level twice");
 
-		if (check_inverse(optarg, &invert, NULL, 0))
+		if (xtables_check_inverse(optarg, &invert, NULL, 0))
 			exit_error(PARAMETER_PROBLEM,
 				   "Unexpected `!' after --log-level");
 
@@ -125,7 +125,7 @@
 			exit_error(PARAMETER_PROBLEM,
 				   "Can't specify --log-prefix twice");
 
-		if (check_inverse(optarg, &invert, NULL, 0))
+		if (xtables_check_inverse(optarg, &invert, NULL, 0))
 			exit_error(PARAMETER_PROBLEM,
 				   "Unexpected `!' after --log-prefix");