improve hook processing macros

- use a get_hooktab() function to determine the hook table.
- PROCESS_HOOK now jumps to a cleanup tag on failure
- add PROCESS_ALL_HOOKS in query.c, to run all hook functions at
  a specified hook point without stopping. this is to be used for
  intiialization and destruction functions that must run in every
  module.
- 'result' is set in PROCESS_HOOK only when a hook function
  interrupts processing.
- revised terminology: a "callback" is now a "hook action"
- remove unused NS_PROCESS_HOOK and NS_PROCESS_HOOK_VOID macros.

lib/ns/tests/query_test.c

@@ -85,7 +85,7 @@ run_sfcache_test(const ns__query_sfcache_test_params_t *test) {
 	query_ctx_t *qctx = NULL;
 	isc_result_t result;
 	ns_hook_t hook = {
-		.callback = ns_test_hook_catch_call,
+		.action = ns_test_hook_catch_call,
 	};
 
 	REQUIRE(test != NULL);
@@ -282,7 +282,7 @@ run_start_test(const ns__query_start_test_params_t *test) {
 	query_ctx_t *qctx = NULL;
 	isc_result_t result;
 	ns_hook_t hook = {
-		.callback = ns_test_hook_catch_call,
+		.action = ns_test_hook_catch_call,
 	};
 
 	REQUIRE(test != NULL);