neuron: block_client: Wait for channel to init

Wait until all conditions are met instead of busy looping to check if
the channels are finished initializing.

Change-Id: I50bd3bad6ccf3f4957ed0a98cdceed45d49fe851
Acked-by: Chris Henroid <chenroid@qti.qualcomm.com>
Signed-off-by: Chris Lew <clew@codeaurora.org>