help.c: wrap wait-only poll() invocation in sleep_millisec()

We want to use the new function elsewhere in a moment.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Reviewed-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

help.c

@@ -372,7 +372,7 @@ const char *help_unknown_cmd(const char *cmd)
 		if (autocorrect > 0) {
 			fprintf_ln(stderr, _("in %0.1f seconds automatically..."),
 				(float)autocorrect/10.0);
-			poll(NULL, 0, autocorrect * 100);
+			sleep_millisec(autocorrect * 100);
 		}
 		return assumed;
 	}