pulseaudio: drop pactl call

It's unnecessary (pa_context_connect will fail in this case) and not
reliable (it's a TOCTOU race).

Refs #52717

Change-Id: I52bb9b3f4234f5a95ce0c05d3b4f0c398093360c

daemon/src/preferences.cpp

@@ -393,10 +393,11 @@ AudioLayer* AudioPreference::createAudioLayer()
 #if HAVE_PULSE
 
     if (audioApi_ == PULSEAUDIO_API_STR) {
-        if (system("pactl info > /dev/null") == 0)
+        try {
             return new PulseLayer(*this);
-        else
-            WARN("pulseaudio daemon not running, falling back to ALSA");
+        } catch (const std::runtime_error &e) {
+            WARN("Could not create pulseaudio layer, falling back to ALSA");
+        }
     }
 
 #endif