tipc: Allow connect() to wait indefinitely

Cause a socket whose TIPC_CONN_TIMEOUT option is zero to wait
indefinitely for a response to a connection request using connect().
Previously, specifying a timeout of 0 ms resulted in an immediate
timeout, which was inconsistent with the behavior specified by Posix
for a socket's receive and send timeout.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>