package/linknx: add lua as optional dependency

Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/linknx/linknx.mk

@@ -9,7 +9,6 @@ LINKNX_SITE = $(call github,linknx,linknx,$(LINKNX_VERSION))
 LINKNX_LICENSE = GPL-2.0+
 LINKNX_INSTALL_STAGING = YES
 LINKNX_CONF_OPTS = \
-	--without-lua \
 	--without-log4cpp \
 	--without-pth-test \
 	--with-pth=$(STAGING_DIR)/usr \
@@ -25,6 +24,13 @@ else
 LINKNX_CONF_OPTS += --without-libcurl
 endif
 
+ifeq ($(BR2_PACKAGE_LUA),y)
+LINKNX_CONF_OPTS += --with-lua
+LINKNX_DEPENDENCIES += lua
+else
+LINKNX_CONF_OPTS += --without-lua
+endif
+
 ifeq ($(BR2_PACKAGE_MYSQL),y)
 LINKNX_CONF_OPTS += --with-mysql=$(STAGING_DIR)/usr
 LINKNX_DEPENDENCIES += mysql