libxtables: prefix/order - libdir

Consolidate the libdir variable initialization code into xtables.c.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
diff --git a/iptables-standalone.c b/iptables-standalone.c
index 3f2432f..c06b286 100644
--- a/iptables-standalone.c
+++ b/iptables-standalone.c
@@ -53,16 +53,7 @@
 	program_name = "iptables";
 	program_version = XTABLES_VERSION;
 
-	lib_dir = getenv("XTABLES_LIBDIR");
-	if (lib_dir == NULL) {
-		lib_dir = getenv("IPTABLES_LIB_DIR");
-		if (lib_dir != NULL)
-			fprintf(stderr, "IPTABLES_LIB_DIR is deprecated, "
-			        "use XTABLES_LIBDIR.\n");
-	}
-	if (lib_dir == NULL)
-		lib_dir = XTABLES_LIBDIR;
-
+	xtables_init();
 #ifdef NO_SHARED_LIBS
 	init_extensions();
 #endif