Migrate to threading_helpers.h

Signed-off-by: Paul Elliott <paul.elliott@arm.com>
diff --git a/tests/include/test/helpers.h b/tests/include/test/helpers.h
index 7c962a2..b2b07cf 100644
--- a/tests/include/test/helpers.h
+++ b/tests/include/test/helpers.h
@@ -35,11 +35,7 @@
 #  endif
 #endif
 
-#if defined(MBEDTLS_THREADING_C) && defined(MBEDTLS_THREADING_PTHREAD) && \
-    defined(MBEDTLS_TEST_HOOKS)
-#define MBEDTLS_TEST_MUTEX_USAGE
-#endif
-
+#include "test/threading_helpers.h"
 #include "mbedtls/platform.h"
 
 #include <stddef.h>
@@ -254,24 +250,6 @@
 #include "test/fake_external_rng_for_test.h"
 #endif
 
-#if defined(MBEDTLS_TEST_MUTEX_USAGE)
-/**
- *  Activate the mutex usage verification framework. See threading_helpers.c for
- *  information.
- *  */
-void mbedtls_test_mutex_usage_init(void);
-
-/**
- *  Deactivate the mutex usage verification framework. See threading_helpers.c
- *  for information.
- */
-void mbedtls_test_mutex_usage_end(void);
-
-/** Call this function after executing a test case to check for mutex usage
- * errors. */
-void mbedtls_test_mutex_usage_check(void);
-#endif /* MBEDTLS_TEST_MUTEX_USAGE */
-
 #if defined(MBEDTLS_TEST_HOOKS)
 /**
  * \brief   Check that only a pure high-level error code is being combined with