remove default destructors & some default constructors

Another ~700 KB reduction in binary size

src/sat/smt/arith_sls.h

@@ -153,7 +153,6 @@ namespace arith {
 
     public:
         sls(solver& s);
-        ~sls() override {}
         void set(sat::ddfw* d);
         void init_search() override;
         void finish_search() override;

src/sat/smt/array_solver.cpp

@@ -88,8 +88,6 @@ namespace array {
         m_constraint->initialize(m_constraint.get(), this);
     }
 
-    solver::~solver() {}
-
     sat::check_result solver::check() {
         force_push();
         // flet<bool> _is_redundant(m_is_redundant, true);

src/sat/smt/array_solver.h

@@ -268,7 +268,6 @@ namespace array {
         void validate_extensionality(euf::enode* s, euf::enode* t) const;
     public:
         solver(euf::solver& ctx, theory_id id);
-        ~solver() override;
         bool is_external(bool_var v) override { return false; }
         void get_antecedents(literal l, sat::ext_justification_idx idx, literal_vector& r, bool probing) override {}
         void asserted(literal l) override {}

src/sat/smt/intblast_solver.h

@@ -103,8 +103,6 @@ namespace intblast {
 
     public:
         solver(euf::solver& ctx);
-        
-        ~solver() override {}
 
         lbool check_axiom(sat::literal_vector const& lits);
         lbool check_core(sat::literal_vector const& lits, euf::enode_pair_vector const& eqs);