package/zynaddsubfx: add portaudio optional dependency

portaudio 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>
(cherry picked from commit e820feba362a29a310ed3a93c8ad5546ceb8a2ee)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/zynaddsubfx/zynaddsubfx.mk

@@ -37,4 +37,11 @@ else
 ZYNADDSUBFX_CONF_OPTS += -DJackEnable=OFF
 endif
 
+ifeq ($(BR2_PACKAGE_PORTAUDIO),y)
+ZYNADDSUBFX_DEPENDENCIES += portaudio
+ZYNADDSUBFX_CONF_OPTS += -DPaEnable=ON
+else
+ZYNADDSUBFX_CONF_OPTS += -DPaEnable=OFF
+endif
+
 $(eval $(cmake-package))