Fix poll.h warning on musl

--- include/adapters/alsa.hpp.orig
+++ include/adapters/alsa.hpp
@@ -4,7 +4,12 @@
 #include <functional>
 #include <string>

+#include <poll.h>
+
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-W#warnings"
 #include <alsa/asoundlib.h>
+#pragma clang diagnostic pop

 #include "common.hpp"
 #include "config.hpp"