log: Add control over log formatting

It is useful to be able to control the output format of log records on the
console. As a starting point, add definitions for controlling which
elements of the log record are displayed. Use function and message as the
default, since these are the most useful fields.

Signed-off-by: Simon Glass <sjg@chromium.org>

common/log.c

@@ -307,6 +307,7 @@ int log_init(void)
 	}
 	gd->flags |= GD_FLG_LOG_READY;
 	gd->default_log_level = LOGL_INFO;
+	gd->log_fmt = LOGF_DEFAULT;
 
 	return 0;
 }