shorten a warning msg
shorten a warning msg

chen0510566/rtabmap,srmanikandasriram/rtabmap,chen0510566/rtabmap,markusgrotz/rtabmap,markusgrotz/rtabmap,MASKOR/rtabmap,MASKOR/rtabmap,srmanikandasriram/rtabmap,chen0510566/rtabmap,markusgrotz/rtabmap,MASKOR/rtabmap,srmanikandasriram/rtabmap