It was waiting for a remote channel, but not for all the interesting
channels we want to check. It can sometimes happen that further away
channels are added before closer ones are added, depending on
propagation path, flush timers and bitcoind poll timers. This now just
checks for all channels, which also reduces the ambiguity of whether
we selected a path solely because we were lacking alternatives.
Signed-off-by: Christian Decker <decker.christian@gmail.com>