This code drains /dev/random only on linux, it totally ignores it on other
platforms. Let's switch to /dev/urandom instead, which is more reliable and
will provide at least as good a result as on non-linux platforms without
failing to start.

--- ./src/crypto/random.c.dist	2018-03-15 20:46:40.521096059 +0100
+++ ./src/crypto/random.c	2018-03-15 20:48:40.291272666 +0100
@@ -227,13 +227,13 @@
 
 	/*
 	 * Try to fetch some more data from the kernel high quality
-	 * /dev/random. There may not be enough data available at this point,
+	 * /dev/urandom. There may not be enough data available at this point,
 	 * so use non-blocking read to avoid blocking the application
 	 * completely.
 	 */
-	fd = open("/dev/random", O_RDONLY | O_NONBLOCK);
+	fd = open("/dev/urandom", O_RDONLY | O_NONBLOCK);
 	if (fd < 0) {
-		wpa_printf(MSG_ERROR, "random: Cannot open /dev/random: %s",
+		wpa_printf(MSG_ERROR, "random: Cannot open /dev/urandom: %s",
 			   strerror(errno));
 		return -1;
 	}
@@ -241,12 +241,12 @@
 	res = read(fd, dummy_key + dummy_key_avail,
 		   sizeof(dummy_key) - dummy_key_avail);
 	if (res < 0) {
-		wpa_printf(MSG_ERROR, "random: Cannot read from /dev/random: "
+		wpa_printf(MSG_ERROR, "random: Cannot read from /dev/urandom: "
 			   "%s", strerror(errno));
 		res = 0;
 	}
 	wpa_printf(MSG_DEBUG, "random: Got %u/%u bytes from "
-		   "/dev/random", (unsigned) res,
+		   "/dev/urandom", (unsigned) res,
 		   (unsigned) (sizeof(dummy_key) - dummy_key_avail));
 	dummy_key_avail += res;
 	close(fd);
@@ -259,7 +259,7 @@
 	}
 
 	wpa_printf(MSG_INFO, "random: Only %u/%u bytes of strong "
-		   "random data available from /dev/random",
+		   "random data available from /dev/urandom",
 		   (unsigned) dummy_key_avail, (unsigned) sizeof(dummy_key));
 
 	if (own_pool_ready >= MIN_READY_MARK ||
@@ -312,12 +312,12 @@
 	res = read(sock, dummy_key + dummy_key_avail,
 		   sizeof(dummy_key) - dummy_key_avail);
 	if (res < 0) {
-		wpa_printf(MSG_ERROR, "random: Cannot read from /dev/random: "
+		wpa_printf(MSG_ERROR, "random: Cannot read from /dev/urandom: "
 			   "%s", strerror(errno));
 		return;
 	}
 
-	wpa_printf(MSG_DEBUG, "random: Got %u/%u bytes from /dev/random",
+	wpa_printf(MSG_DEBUG, "random: Got %u/%u bytes from /dev/urandom",
 		   (unsigned) res,
 		   (unsigned) (sizeof(dummy_key) - dummy_key_avail));
 	dummy_key_avail += res;
@@ -412,14 +412,14 @@
 	if (random_fd >= 0)
 		return;
 
-	random_fd = open("/dev/random", O_RDONLY | O_NONBLOCK);
+	random_fd = open("/dev/urandom", O_RDONLY | O_NONBLOCK);
 	if (random_fd < 0) {
-		wpa_printf(MSG_ERROR, "random: Cannot open /dev/random: %s",
+		wpa_printf(MSG_ERROR, "random: Cannot open /dev/urandom: %s",
 			   strerror(errno));
 		return;
 	}
 	wpa_printf(MSG_DEBUG, "random: Trying to read entropy from "
-		   "/dev/random");
+		   "/dev/urandom");
 
 	eloop_register_read_sock(random_fd, random_read_fd, NULL, NULL);
 #endif /* __linux__ */