Add satmode detection for Icom rigs like IC9700

In satmode VFOB/Sub now maps to SubA (2nd VFO)
https://github.com/Hamlib/Hamlib/issues/621

rigs/icom/icom.c

@@ -2107,6 +2107,11 @@ int icom_set_vfo(RIG *rig, vfo_t vfo)
     {
         // If we're being asked for B/Sub but we are a MainA/MainB rig change it
         vfo = RIG_VFO_MAIN_B;
+        // If we're in satmode for rigs like IC9700 we want the 2nd VFO
+        if (rig->state.cache.satmode)
+        {
+            vfo = RIG_VFO_SUB_A;
+        }
     }
     else if ((vfo == RIG_VFO_A || vfo == RIG_VFO_B) && !VFO_HAS_A_B && VFO_HAS_MAIN_SUB)
     {

rigs/icom/icom.h

@@ -30,7 +30,7 @@
 #include <sys/time.h>
 #endif
 
-#define BACKEND_VER "20210319"
+#define BACKEND_VER "20210320"
 
 /*
  * defines used by comp_cal_str in rig.c