Fix Ubuntu compile error in udp_proxy.c

Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
diff --git a/programs/test/udp_proxy.c b/programs/test/udp_proxy.c
index 41a90a9..6ffd3cd 100644
--- a/programs/test/udp_proxy.c
+++ b/programs/test/udp_proxy.c
@@ -73,9 +73,10 @@
 #endif
 #endif /* _MSC_VER */
 #else /* ( _WIN32 || _WIN32_WCE ) && !EFIX64 && !EFI32 */
-#if defined(MBEDTLS_HAVE_TIME)
+#if defined(MBEDTLS_HAVE_TIME) || (defined(MBEDTLS_TIMING_C) && !defined(MBEDTLS_TIMING_ALT))
 #include <sys/time.h>
 #endif
+#include <sys/select.h>
 #include <sys/types.h>
 #include <unistd.h>
 #endif /* ( _WIN32 || _WIN32_WCE ) && !EFIX64 && !EFI32 */