use NULL to load plugins from default plugin directory

src/pluto/Makefile.am

@@ -68,7 +68,6 @@ AM_CFLAGS = \
 -DIPSEC_CONFDIR=\"${sysconfdir}\" \
 -DIPSEC_PIDDIR=\"${piddir}\" \
 -DSHARED_SECRETS_FILE=\"${confdir}/ipsec.secrets\" \
--DIPSEC_PLUGINDIR=\"${plugindir}\" \
 -DPLUGINS=\""${pluto_plugins}\"" \
 -DSTRONGSWAN_CONF=\"${strongswan_conf}\" \
 -DPKCS11_DEFAULT_LIB=\"${default_pkcs11}\" \

src/pluto/plutomain.c

@@ -652,7 +652,7 @@ int main(int argc, char **argv)
 	}
 
 	/* load plugins, further infrastructure may need it */
-	if (!lib->plugins->load(lib->plugins, IPSEC_PLUGINDIR,
+	if (!lib->plugins->load(lib->plugins, NULL,
 			lib->settings->get_str(lib->settings, "pluto.load", PLUGINS)))
 	{
 		exit(SS_RC_INITIALIZATION_FAILED);