Adding early key computation config check

diff --git a/include/mbedtls/check_config.h b/include/mbedtls/check_config.h
index 13bd50c..97dcc02 100644
--- a/include/mbedtls/check_config.h
+++ b/include/mbedtls/check_config.h
@@ -914,6 +914,11 @@
 #error "MBEDTLS_DELAYED_SERVER_CERT_VERIFICATION can only be used with MBEDTLS_SSL_KEEP_PEER_CERTIFICATE"
 #endif
 
+
+#if defined(MBEDTLS_EARLY_KEY_COMPUTATION) && !defined(MBEDTLS_USE_TINYCRYPT)
+#error "MBEDTLS_EARLY_KEY_COMPUTATION can only be used with MBEDTLS_USE_TINYCRYPT"
+#endif
+
 /*
  * Note: the dependency on TinyCrypt is reflected in several ways in the code:
  *