cmake: Add new tests to test suite

Bring functionality of the cmake build system up to autotools.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Change-Id: I2231b51cfd52460fb525b5af6893b0474508859b
diff --git a/tests/test_serial.c b/tests/test_serial.c
index 905f664..9691037 100644
--- a/tests/test_serial.c
+++ b/tests/test_serial.c
@@ -2,7 +2,9 @@
 
 #define _GNU_SOURCE
 
+#if HAVE_CONFIG_H
 #include "config.h"
+#endif
 
 #include "libmctp-log.h"
 #include "libmctp-serial.h"