Fix icom_get_mode for rigs with 1-byte mode_len

https://github.com/Hamlib/Hamlib/issues/522

rigs/icom/icom.c

@@ -1911,7 +1911,8 @@ int icom_get_mode(RIG *rig, vfo_t vfo, rmode_t *mode, pbwidth_t *width)
     /*
      * modebuf should contain Cn,Data area
      */
-    mode_len--;
+    // when mode gets here it should be 2 or 1
+    // mode_len--;
 
     if (mode_len != 2 && mode_len != 1)
     {

rigs/icom/icom.h

@@ -30,7 +30,7 @@
 #include <sys/time.h>
 #endif
 
-#define BACKEND_VER "20210120"
+#define BACKEND_VER "20210129"
 
 /*
  * defines used by comp_cal_str in rig.c