sandbox: Disable Ctrl-C

This is not supported properly on sandbox, and interferes with running
tests, since when a test script is piped in, some commands will call
ctrlc() which will drop characters from the test script.

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

common/console.c

@@ -524,6 +524,7 @@ static int ctrlc_disabled = 0;	/* see disable_ctrl() */
 static int ctrlc_was_pressed = 0;
 int ctrlc(void)
 {
+#ifndef CONFIG_SANDBOX
 	if (!ctrlc_disabled && gd->have_console) {
 		if (tstc()) {
 			switch (getc()) {
@@ -535,6 +536,8 @@ int ctrlc(void)
 			}
 		}
 	}
+#endif
+
 	return 0;
 }
 /* Reads user's confirmation.