nrf_rpc: Improve binding robustness

The failure to bind the IPC channel is not an unrecoverable error. The
IPC state should remain in WAITING state when binding was not completed
on time.

Signed-off-by: Rafał Kuźnia <rafal.kuznia@nordicsemi.no>

subsys/nrf_rpc/nrf_rpc_ipc.c

@@ -169,7 +169,6 @@ static int send(const struct nrf_rpc_tr *transport, const uint8_t *data, size_t
 	case NRF_RPC_IPC_STATE_WAITING:
 		if (!k_event_wait(&endpoint->ept_bond, 0x01, false,
 				ipc_config->endpoint.timeout)) {
-			ipc_config->state = NRF_RPC_IPC_STATE_ERROR;
 			LOG_ERR("IPC endpoint bond timeout");
 			return -NRF_EPIPE;
 		}