mcbts: Add multi-ARFCN radio support

Add new radio interface "radioInterfaceMulti" for multi-carrier
support.

Only USRP B200/B210 devices are supported because of sample
rate requirements (3.2 Msps).

Only 4 SPS operation Tx/RX is supported.

8-PSK is supported.

Other options may be added at a later time

Signed-off-by: Tom Tsou <tom.tsou@ettus.com>
diff --git a/Transceiver52M/radioDevice.h b/Transceiver52M/radioDevice.h
index a992483..142fcf6 100644
--- a/Transceiver52M/radioDevice.h
+++ b/Transceiver52M/radioDevice.h
@@ -23,6 +23,7 @@
 #endif
 
 #define GSMRATE       (1625e3/6)
+#define MCBTS_SPACING  800000.0
 
 /** a 64-bit virtual timestamp for radio data */
 typedef unsigned long long TIMESTAMP;
@@ -39,6 +40,7 @@
     NORMAL,
     RESAMP_64M,
     RESAMP_100M,
+    MULTI_ARFCN,
     DIVERSITY,
   };