tipc: Remove non-executable code to handle broadcast bearer congestion

Eliminates code associated with the sending of unsent broadcast link
traffic when the broadcast pseudo-bearer becomes unblocked following a
temporary congestion situation. This code is non-executable because the
broadcast pseudo-bearer never becomes blocked [see tipc_bcbearer_send()].

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>