keepalive: add optional json-c dependency

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/keepalived/keepalived.mk

@@ -13,6 +13,13 @@ KEEPALIVED_LICENSE_FILES = COPYING
 KEEPALIVED_AUTORECONF = YES
 KEEPALIVED_CONF_OPTS += --disable-dbus
 
+ifeq ($(BR2_PACKAGE_JSON_C),y)
+KEEPALIVED_DEPENDENCIES += json-c
+KEEPALIVED_CONF_OPTS += --enable-json
+else
+KEEPALIVED_CONF_OPTS += --disable-json
+endif
+
 ifeq ($(BR2_PACKAGE_LIBNL)$(BR2_PACKAGE_LIBNFNETLINK),yy)
 KEEPALIVED_DEPENDENCIES += libnl libnfnetlink
 KEEPALIVED_CONF_OPTS += --enable-libnl