Fix missing-prototype errors in tests/suites
Signed-off-by: Michael Schuster <michael@schuster.ms>
diff --git a/tests/suites/test_suite_platform.function b/tests/suites/test_suite_platform.function
index c65d011..5d49e52 100644
--- a/tests/suites/test_suite_platform.function
+++ b/tests/suites/test_suite_platform.function
@@ -18,7 +18,7 @@
#else
#include <unistd.h>
#endif
-void sleep_ms(int milliseconds)
+static void sleep_ms(int milliseconds)
{
#if defined(_WIN32) || defined(WIN32) || defined(__CYGWIN__) || \
defined(__MINGW32__) || defined(_WIN64)