AP_InternalError: add a bit for infinite recursion in switch_full_sector

libraries/AP_InternalError/AP_InternalError.h

@@ -53,7 +53,8 @@ public:
         bitmask_range               = (1U << 17),  // 0x20000  131072
         gcs_offset                  = (1U << 18),  // 0x40000  262144
         i2c_isr                     = (1U << 19),  // 0x80000  524288
-        flow_of_control             = (1U << 20), // for generic we-should-never-get-here situations
+        flow_of_control             = (1U << 20),  //0x100000  1048576 for generic we-should-never-get-here situations
+        switch_full_sector_recursion= (1U << 21),  //0x200000  2097152
     };
 
     void error(const AP_InternalError::error_t error);