sd-daemon: support for building sd-daemon.c with Bionic (Android)

sd-daemon.h is a drop-in file, so we should make sure it doesn't break
builds for anybody.

https://bugs.freedesktop.org/show_bug.cgi?id=42675

src/sd-daemon.c

@@ -32,7 +32,11 @@
 #include <sys/stat.h>
 #include <sys/socket.h>
 #include <sys/un.h>
+#ifdef __BIONIC__
+#include <linux/fcntl.h>
+#else
 #include <sys/fcntl.h>
+#endif
 #include <netinet/in.h>
 #include <stdlib.h>
 #include <errno.h>