Fix fd range for select on Windows

Fix mbedtls_net_poll() and mbedtls_net_recv_timeout() often failing with
MBEDTLS_ERR_NET_POLL_FAILED on Windows: they were testing that the file
descriptor is in range for fd_set, but on Windows socket descriptors are not
limited to a small range. Fixes #4465.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/ChangeLog.d/winsock.txt b/ChangeLog.d/winsock.txt
new file mode 100644
index 0000000..0b42e69
--- /dev/null
+++ b/ChangeLog.d/winsock.txt
@@ -0,0 +1,4 @@
+Bugfix
+   * Fix mbedtls_net_poll() and mbedtls_net_recv_timeout() often failing with
+     MBEDTLS_ERR_NET_POLL_FAILED on Windows. Fixes #4465.
+