Reset sndiod initialization flag on disconnects

If the connection is lost to the sndiod(8) daemon reset the
initialization to allow for a graceful restart.

components/volume.c

@@ -161,6 +161,7 @@
 				if (sioctl_revents(hdl, pfds) & POLLHUP) {
 					warn("sndio: disconnected");
 					cleanup();
+					initialized = 0;
 					return NULL;
 				}
 			}