cmake MRPT_HAS_OPENNI2 examples

MRPT/mrpt cmakemodules/script_openni2.cmake :35 

option(MRPT_HAS_OPENNI2 "Support for the OpenNI2 library" ${DEFAULT_MRPT_HAS_OPENNI2})

MRPT/mrpt cmakemodules/script_openni2.cmake :72 

message(FATAL_ERROR "OpenNI2 not found: Either correctly set OPENNI2_INCLUDE_DIR and OPENNI2_LIBRARY or uncheck MRPT_HAS_OPENNI2")