etests: remove MBEDTLS_DHM_C/DHM occurrencies

Signed-off-by: Valerio Setti <valerio.setti@nordicsemi.no>
diff --git a/tests/include/test/certs.h b/tests/include/test/certs.h
index db69536..31f4477 100644
--- a/tests/include/test/certs.h
+++ b/tests/include/test/certs.h
@@ -1,7 +1,7 @@
 /**
  * \file certs.h
  *
- * \brief Sample certificates and DHM parameters for testing
+ * \brief Sample certificates for testing
  */
 /*
  *  Copyright The Mbed TLS Contributors