don't break the process, actually reboot!

Reference: /n/patches.lsub.org/patch/rebootreboot
Date: Sun Oct 28 18:17:32 CET 2012
Signed-off-by: quanstro@quanstro.net

--- /sys/src/nix/port/devcons.c	Thu Jul 19 10:16:25 2012
+++ /sys/src/nix/port/devcons.c	Sun Oct 28 17:23:43 2012
@@ -1166,7 +1166,6 @@
 			rebootcmd(cb->nf-1, cb->f+1);
 			break;
 		case CMpanic:
-			*(ulong*)0=0;
 			panic("/dev/reboot");
 		}
 		poperror();