I haven't looked at this particular section of the law; but I don't see how that could be possible. If you have notice that entry on to a property is forbidden, then continuing to do so is criminal trespass (and committing criminal trespass while armed is a Class A Misdemeanor in Texas). I don't see how the 30.06 sign could be effective notice to CHL holders; but not effective notice to others that entry is forbidden.
Pretty much only covers license holders
§ 30.06. TRESPASS BY HOLDER OF LICENSE TO CARRY CONCEALED