ECDH: Fix whitespace and doxygen comment
diff --git a/include/mbedtls/config.h b/include/mbedtls/config.h
index 5443dd2..1e28932 100644
--- a/include/mbedtls/config.h
+++ b/include/mbedtls/config.h
@@ -3576,7 +3576,7 @@
  */
 //#define MBEDTLS_PLATFORM_GMTIME_R_ALT
 
-/*
+/**
  * \def MBEDTLS_ECDH_VARIANT_EVEREST_ENABLED
  *
  * Enable the verified implementations of crypto primitives