cmake LMMS_HAVE_LV2 examples

LMMS/lmms plugins/Lv2Effect/CMakeLists.txt :9 

ENDIF(LMMS_HAVE_LV2)

LMMS/lmms plugins/Lv2Instrument/CMakeLists.txt :7 

ENDIF(LMMS_HAVE_LV2)