analyzer: fix memory leaks

analyzer: fix memory leaks

These leaks all relate to logging within -fdump-analyzer[-stderr]
or are one-time leaks; seen with valgrind.

gcc/analyzer/ChangeLog:
	* checker-path.cc (state_change_event::get_desc): Call maybe_free
	on label_text temporaries.
	* diagnostic-manager.cc
	(diagnostic_manager::prune_for_sm_diagnostic): Likewise.
	* engine.cc (exploded_graph::~exploded_graph): Fix leak of
	m_per_point_data and m_per_call_string_data values.  Simplify
	cleanup of m_per_function_stats and m_per_point_data values.
	(feasibility_state::maybe_update_for_edge): Fix leak of result of
	superedge::get_description.
	* region-model-manager.cc
	(region_model_manager::~region_model_manager): Move cleanup of
	m_setjmp_values to match the ordering of the fields within
	region_model_manager.  Fix leak of values within
	m_repeated_values_map, m_bits_within_values_map,
	m_asm_output_values_map, and m_const_fn_result_values_map.

Signed-off-by: David Malcolm <dmalcolm@redhat.com>