Minor tweak to "waitmode" in libreboot.
Previously ISUP and TBFAILED were the two states that signified that a node had rebooted to the satisfaction of libreboot (with waitmode==1). Add RELOAD/RELOADING to that list since the frisbee MFS never sends either of ISUP or TBFAILED. Required a modification to TBNodeStateWait() to allow waiting for an op-mode/state combo as well as just a state. I made this change in anticipation that it would be useful for more responsive monitoring of failure in tbswap/os_load. But now I am no so sure.