AP_Logger: correct comment about reserved range for vehicle IDs

Author: peterbarker

libraries/AP_Logger/LogStructure.h

@@ -1309,7 +1309,7 @@ LOG_STRUCTURE_FROM_AIS \
     { LOG_MOTBATT_MSG, sizeof(log_MotBatt), \
       "MOTB", "QfffffB",  "TimeUS,LiftMax,BatVolt,ThLimit,ThrAvMx,ThrOut,FailFlags", "s------", "F------" , true }
 
-// message types 0 to 63 reserved for vehicle specific use
+// message types 0 to 31 reserved for vehicle-specific use
 
 // message types for common messages
 enum LogMessages : uint8_t {