Fix build error in CI about test_fail_if_psa_leaking

During test of component build_arm_linux_gnueabi_gcc_arm5vte and
build_arm_none_eabi_gcc_m0plus. It fails with
 - error: implicit declaration of function
   ‘test_fail_if_psa_leaking’

It happens because test_fail_if_psa_leaking is defined in
helpers.function. This block of code is not converted into C code
while compiling ssl_helpers.c. The function has been moved to
psa_crypto_helpers.c in order to fix this build error.

Signed-off-by: Yanray Wang <yanray.wang@arm.com>
diff --git a/tests/src/psa_crypto_helpers.c b/tests/src/psa_crypto_helpers.c
index 06274d3..77c2f89 100644
--- a/tests/src/psa_crypto_helpers.c
+++ b/tests/src/psa_crypto_helpers.c
@@ -138,4 +138,15 @@
     return updated_usage;
 }
 
+int mbedtls_test_fail_if_psa_leaking(int line_no, const char *filename)
+{
+    const char *msg = mbedtls_test_helper_is_psa_leaking();
+    if (msg == NULL) {
+        return 0;
+    } else {
+        mbedtls_test_fail(msg, line_no, filename);
+        return 1;
+    }
+}
+
 #endif /* MBEDTLS_PSA_CRYPTO_C */