Add a disabled CMAC define in the no-entropy configuration
diff --git a/configs/config-no-entropy.h b/configs/config-no-entropy.h
index b4a0930..7d34ad5 100644
--- a/configs/config-no-entropy.h
+++ b/configs/config-no-entropy.h
@@ -82,6 +82,7 @@
 #define MBEDTLS_X509_USE_C
 #define MBEDTLS_X509_CRT_PARSE_C
 #define MBEDTLS_X509_CRL_PARSE_C
+//#define MBEDTLS_CMAC_C
 
 /* Miscellaneous options */
 #define MBEDTLS_AES_ROM_TABLES