analyzer: fix build with gcc 4.4 (PR 93276)

This patch fixes various build failures seen with gcc 4.4

gcc prior to 4.6 complains about:

  error: #pragma GCC diagnostic not allowed inside functions

for various uses of PUSH_IGNORE_WFORMAT and POP_IGNORE_WFORMAT.
This patch makes them a no-op with such compilers.

The patch also fixes various errors with template base initializers
and redundant uses of "typename" that older g++ implementations
can't cope with.

gcc/analyzer/ChangeLog:
	PR analyzer/93276
	* analyzer.h (PUSH_IGNORE_WFORMAT, POP_IGNORE_WFORMAT): Guard these
	macros with GCC_VERSION >= 4006, making them no-op otherwise.
	* engine.cc (exploded_edge::exploded_edge): Specify template for
	base class initializer.
	(exploded_graph::add_edge): Specify template when chaining up to
	base class add_edge implementation.
	(viz_callgraph_node::dump_dot): Drop redundant "typename".
	(viz_callgraph_edge::viz_callgraph_edge): Specify template for
	base class initializer.
	* program-state.cc (sm_state_map::clone_with_remapping): Drop
	redundant "typename".
	(sm_state_map::print): Likewise.
	(sm_state_map::hash): Likewise.
	(sm_state_map::operator==): Likewise.
	(sm_state_map::remap_svalue_ids): Likewise.
	(sm_state_map::on_svalue_purge): Likewise.
	(sm_state_map::validate): Likewise.
	* program-state.h (sm_state_map::iterator_t): Likewise.
	* supergraph.h (superedge::superedge): Specify template for base
	class initializer.

gcc/ChangeLog:
	PR analyzer/93276
	* digraph.cc (test_edge::test_edge): Specify template for base
	class initializer.