Generalize builtin specification in JIT and add support for cos and exp * src/ov-builtin.cc (octave_builtin::function): New function. * src/ov-builtin.h (octave_builtin::function): New declaration. * src/pt-jit.cc (gripe_bad_result, octave_jit_call, jit_typeinfo::add_builtin, jit_typeinfo::register_intrinsic, jit_typeinfo::find_builtin, jit_typeinfo::register_generic): New function. (jit_typeinfo::jit_typeinfo): Generalize builtin specification and add support for cos and exp. (jit_typeinfo::create_function): New overload. * src/pt-jit.h (overload::overload, jit_function::add_overload, jit_typeinfo::create_function): New overload. (jit_typeinfo::add_builtin, jit_typeinfo::register_intrinsic, jit_typeinfo::register_generic, jit_typeinfo::find_builtin): New declaration.