util/spkmodem_recv: Return errno in main

This is a good general practise, to catch errors.

Any errors found can then be handled in code.

Signed-off-by: Leah Rowe <leah@libreboot.org>

util/spkmodem_recv/spkmodem-recv.c

@@ -39,7 +39,7 @@ main(int argc, char *argv[])
 	while (!feof(stdin))
 		print_chars();
 
-	return 0;
+	return errno;
 }
 
 void