minor bugfix for USRP init

targets/ARCH/USRP/USERSPACE/LIB/usrp_lib.cpp

@@ -711,8 +711,12 @@ extern "C" {
   for(i=0;i<s->usrp->get_tx_num_channels();i++) {
     if (i<openair0_cfg[0].tx_num_channels) {
       s->usrp->set_tx_bandwidth(openair0_cfg[0].tx_bw,i);
-      s->usrp->set_rx_bandwidth(openair0_cfg[0].rx_bw,i);
       printf("Setting tx freq/gain on channel %lu/%lu: BW %f (readback %f)\n",i,s->usrp->get_tx_num_channels(),openair0_cfg[0].tx_bw/1e6,s->usrp->get_tx_bandwidth(i)/1e6);
+    }
+  }
+  for(i=0;i<s->usrp->get_rx_num_channels();i++) {
+    if (i<openair0_cfg[0].rx_num_channels) {
+      s->usrp->set_rx_bandwidth(openair0_cfg[0].rx_bw,i);
       printf("Setting rx freq/gain on channel %lu/%lu : BW %f (readback %f)\n",i,s->usrp->get_rx_num_channels(),openair0_cfg[0].rx_bw/1e6,s->usrp->get_rx_bandwidth(i)/1e6);
     }
   }