package/zynaddsubfx: add jack{1, 2} optional dependency

jack{1,2} is an optional dependency (enabled by default) since the
addition of the package in commit
18a863063735e2c658fa6947a4e540e9dda6c431

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

package/zynaddsubfx/zynaddsubfx.mk

@@ -30,4 +30,11 @@ else
 ZYNADDSUBFX_CONF_OPTS += -DAlsaEnable=OFF
 endif
 
+ifeq ($(BR2_PACKAGE_JACK1)$(BR2_PACKAGE_JACK2),y)
+ZYNADDSUBFX_DEPENDENCIES += $(if $(BR2_PACKAGE_JACK1),jack1,jack2)
+ZYNADDSUBFX_CONF_OPTS += -DJackEnable=ON
+else
+ZYNADDSUBFX_CONF_OPTS += -DJackEnable=OFF
+endif
+
 $(eval $(cmake-package))