ssl_helpers: remove guard for rng_get()

After adding a check in ssl_conf_check(), we have configured RNG via
mbedtls_ssl_conf_rng() for TLS tests in both test_suite_ssl.function
and test_suite_debug.function. As a result, rng_get() is not only
available when MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED enabled.
Therefore, we remove the guard for rng_get() to make it accessible for
TLS tests which have call for mbedtls_ssl_setup().

Signed-off-by: Yanray Wang <yanray.wang@arm.com>
diff --git a/tests/include/test/ssl_helpers.h b/tests/include/test/ssl_helpers.h
index b45e969..9493b69 100644
--- a/tests/include/test/ssl_helpers.h
+++ b/tests/include/test/ssl_helpers.h
@@ -193,9 +193,7 @@
 
 #endif /* MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED */
 
-#if defined(MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED)
 int rng_get(void *p_rng, unsigned char *output, size_t output_len);
-#endif
 
 /*
  * This function can be passed to mbedtls to receive output logs from it. In
diff --git a/tests/src/test_helpers/ssl_helpers.c b/tests/src/test_helpers/ssl_helpers.c
index 549a4ff..de76b09 100644
--- a/tests/src/test_helpers/ssl_helpers.c
+++ b/tests/src/test_helpers/ssl_helpers.c
@@ -12,8 +12,6 @@
 #include "md_psa.h"
 
 #if defined(MBEDTLS_SSL_TLS_C)
-#if defined(MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED)
-static int rng_seed = 0xBEEF;
 int rng_get(void *p_rng, unsigned char *output, size_t output_len)
 {
     (void) p_rng;
@@ -23,7 +21,6 @@
 
     return 0;
 }
-#endif
 
 void mbedtls_test_ssl_log_analyzer(void *ctx, int level,
                                    const char *file, int line,
@@ -46,6 +43,8 @@
     mbedtls_test_handshake_test_options *opts)
 {
 #if defined(MBEDTLS_SSL_HANDSHAKE_WITH_CERT_ENABLED)
+    int rng_seed = 0xBEEF;
+
     srand(rng_seed);
     rng_seed += 0xD0;
 #endif