Silence compiler warning in test
Happens with some, but not all, versions of GCC/Glibc.
diff --git a/tests/suites/test_suite_x509write.function b/tests/suites/test_suite_x509write.function
index 4aad85f..3d09d85 100644
--- a/tests/suites/test_suite_x509write.function
+++ b/tests/suites/test_suite_x509write.function
@@ -52,7 +52,7 @@
f = fopen( {cert_req_check_file}, "r" );
TEST_ASSERT( f != NULL );
- fread( check_buf, 1, 4000, f );
+ (void) fread( check_buf, 1, 4000, f );
fclose( f );
pem_init( &pem );