removed unnecessary compiler version check for building GafferRenderMan
removed unnecessary compiler version check for building GafferRenderMan

ImageEngine/gaffer,hradec/gaffer,chippey/gaffer,ImageEngine/gaffer,boberfly/gaffer,boberfly/gaffer,andrewkaufman/gaffer,GafferHQ/gaffer,boberfly/gaffer,lucienfostier/gaffer,ivanimanishi/gaffer,appleseedhq/gaffer,hradec/gaffer,ivanimanishi/gaffer,ivanimanishi/gaffer,hradec/gaffer,goddardl/gaffer,ImageEngine/gaffer,andrewkaufman/gaffer,lucienfostier/gaffer,andrewkaufman/gaffer,appleseedhq/gaffer,GafferHQ/gaffer,appleseedhq/gaffer,goddardl/gaffer,johnhaddon/gaffer,andrewkaufman/gaffer,lucienfostier/gaffer,chippey/gaffer,chippey/gaffer,johnhaddon/gaffer,johnhaddon/gaffer,chippey/gaffer,johnhaddon/gaffer,boberfly/gaffer,lucienfostier/gaffer,andrewkaufman/gaffer,GafferHQ/gaffer,GafferHQ/gaffer,goddardl/gaffer,hradec/gaffer,appleseedhq/gaffer,goddardl/gaffer,GafferHQ/gaffer,ImageEngine/gaffer,ivanimanishi/gaffer,hradec/gaffer,johnhaddon/gaffer