add tests to increase test coverage

lib/cmp_icu.c

lib/cmp_max_used_bits.c

lib/cmp_support.c

test/cmp_data_types/test_cmp_data_types.c

test/cmp_entity/test_cmp_entity.c

test/cmp_icu/test_decmp.c

test/cmp_max_used_bits/test_cmp_max_used_bits_list.c

test/cmp_rdcu_cfg/test_cmp_rdcu_cfg.c