Replace custom isc_boolean_t with C standard bool type

doc/design/compression

@@ -110,7 +110,7 @@ Functions:
 	struct dns_compress {
 		unsigned int allowed;	/* Allowed methods. */
 		unsigned int rdata;	/* Start of local rdata */
-		isc_boolean_t global16;	/* 16 bit offsets allowed */
+		bool global16;	/* 16 bit offsets allowed */
 		dns_rbt_t *local;	/* Local RBT */
 		dns_rbt_t *global;	/* Global RBT */
 		isc_mem_t *mctx;	/* Required by RBT */
@@ -118,12 +118,12 @@ Functions:
 
 	sets allowed based on the value of edns.
 
-	isc_boolean_t
+	bool
 	dns_compress_findglobal(dns_compress_t *cctx, dns_name_t *name,
 				dns_name_t *prefix, dns_name_t *suffix,
 				uint16_t *offset, isc_buffer_t *workspace);
 
-	isc_boolean_t
+	bool
 	dns_compress_findlocal(dns_compress_t *cctx, dns_name_t *name,
 			       dns_name_t *prefix, dns_name_t *suffix,
 			       uint16_t *offset, isc_buffer_t *workspace);

doc/design/decompression

@@ -45,14 +45,14 @@ Types:
 		int		edns;
 		dns_name_t 	owner_name;
 		unsigned int	rdata;
-		isc_boolean_t	strict;
+		bool	strict;
 	}
 
 Functions:
 
 	void
 	dns_decompress_init(dns_decompress_t *dctx, int edns,
-			    isc_boolean_t strict);
+			    bool strict);
 	initalise dctx
 	dctx->ownername is invalidated
 
@@ -87,12 +87,12 @@ Functions:
 
 	returns dctx->edns
 
-	isc_boolean_t
+	bool
 	dns_decompress_strict(dns_decompress_t *dctx);
 
 	returns dctx->strict
 
 	dns_result_t
 	dns_name_fromwire(dns_name_t *name, isc_buffer_t *source,
-			  dns_decompress_t *dctx, isc_boolean_t downcase,
+			  dns_decompress_t *dctx, bool downcase,
 			  isc_buffer_t *target)

doc/design/zone

@@ -238,7 +238,7 @@ Functions:
 
     dns_zone_setxfracl(dns_zone_t *, dns_acl_t *)
 
-    dns_zone_addnotify(dns_zone_t *, isc_sockaddr_t *addr, isc_boolean_t perm);
+    dns_zone_addnotify(dns_zone_t *, isc_sockaddr_t *addr, bool perm);
 
     dns_zone_clearnotify(dns_zone_t *)