pulseaudio: alsa backend needs pcm+mixer apis

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

package/multimedia/pulseaudio/pulseaudio.mk

@@ -29,6 +29,11 @@ PULSEAUDIO_DEPENDENCIES = \
 	$(if $(BR2_PACKAGE_FFTW),fftw) \
 	$(if $(BR2_PACKAGE_ORC),orc)
 
+# pulseaudio alsa backend needs pcm/mixer apis
+ifneq ($(BR2_PACKAGE_ALSA_LIB_PCM)$(BR2_PACKAGE_ALSA_LIB_MIXER),yy)
+PULSEAUDIO_CONF_OPT += --disable-alsa
+endif
+
 ifneq ($(BR2_PACKAGE_VALA),y)
 define PULSEAUDIO_REMOVE_VALA
 	rm -rf $(TARGET_DIR)/usr/share/vala