Fix moc_predefs.h gen when ccache is enabled through...
Fix moc_predefs.h gen when ccache is enabled through -DCMAKE_CXX_COMPILER=ccache CMAKE_CXX_COMPILER_ARG1=g++
Fix moc_predefs.h gen when ccache is enabled through -DCMAKE_CXX_COMPILER=ccache CMAKE_CXX_COMPILER_ARG1=g++