This means that CMake tries to automatically find the Freetype library on your disk, but does not find it. You will need to manually tell cmake where the .so file corresponding to FREETYPE_LIBRARY, and where the include directory for is located FREETYPE_INCLUDE_DIRS.
, /foo/bar/freetype, cmake, , :
-DFREETYPE_LIBRARY=/foo/bar/freetype/freetype.so -DFREETYPE_INCLUDE_DIRS=/foo/bar/freetype/include
Freetype , , , .