Remove FLINT_LIB during make clean.
Remove FLINT_LIB during make clean.

jpflori/flint2,wbhart/flint2,dsroche/flint2,fredrik-johansson/flint2,wbhart/flint2,jpflori/flint2,wbhart/flint2,dsroche/flint2,fredrik-johansson/flint2,fredrik-johansson/flint2,jpflori/flint2,dsroche/flint2,dsroche/flint2,jpflori/flint2