soapy: disable LimeSDR specific modifciations

this turns off some Lime specific tweaks that we did, for example
turning off streaming before changing the sampling rate.

those are now implemented inside the LimeSuite (as of 20.01)
and are no longer required here

patch also disable the explicit BW setting and async background thread

lib/src/phy/rf/rf_soapy_imp.c

@@ -35,11 +35,11 @@
 #include <SoapySDR/Version.h>
 #include <Types.h>
 
-#define HAVE_ASYNC_THREAD 1
+#define HAVE_ASYNC_THREAD 0
 
-#define STOP_STREAM_BEFORE_RATE_CHANGE 1
+#define STOP_STREAM_BEFORE_RATE_CHANGE 0
 #define USE_TX_MTU 0
-#define SET_RF_BW 1
+#define SET_RF_BW 0
 
 #define PRINT_RX_STATS 0
 #define PRINT_TX_STATS 0
@@ -615,14 +615,13 @@ double rf_soapy_set_rx_srate(void* h, double rate)
       double bw = rate * 0.75;
       bw        = SRSLTE_MIN(bw, bw_range[k].maximum);
       bw        = SRSLTE_MAX(bw, bw_range[k].minimum);
-      bw        = SRSLTE_MAX(bw, 2.5e6); // For the Lime to avoid warnings
       if (SoapySDRDevice_setBandwidth(handler->device, SOAPY_SDR_RX, i, bw) != 0) {
         printf("setBandwidth fail: %s\n", SoapySDRDevice_lastError());
         return SRSLTE_ERROR;
       }
       printf("Set Rx bandwidth to %.2f MHz\n", SoapySDRDevice_getBandwidth(handler->device, SOAPY_SDR_RX, i) / 1e6);
     }
-#endif
+#endif // SET_RF_BW
   }
 
 #if STOP_STREAM_BEFORE_RATE_CHANGE
@@ -668,7 +667,7 @@ double rf_soapy_set_tx_srate(void* h, double rate)
       }
       printf("Set Tx bandwidth to %.2f MHz\n", SoapySDRDevice_getBandwidth(handler->device, SOAPY_SDR_TX, i) / 1e6);
     }
-#endif
+#endif // SET_RF_BW
   }
 
 #if STOP_STREAM_BEFORE_RATE_CHANGE