remove hack in syslog.h that resulted in aliasing violations

this issue affected the prioritynames and facilitynames arrays which
are only provided when requested (usually by syslogd implementations)
and which are presently defined as compound literals. the aliasing
violation seems to have been introduced as a workaround for bad
behavior by gcc's -Wwrite-strings option, but it caused compilers to
completely optimize out the contents of prioritynames and
facilitynames since, under many usage cases, the aliasing rules prove
that the contents are never accessed.

(cherry picked from commit 70d9c303b3115ab0fe6060ba0f7b0e4c0a2320b7)

include/syslog.h

@@ -69,21 +69,17 @@ void vsyslog (int, const char *, va_list);
 #if defined(SYSLOG_NAMES)
 #define	INTERNAL_NOPRI 0x10
 #define	INTERNAL_MARK (LOG_NFACILITIES<<3)
-struct __CODE {
-	const char *c_name;
-	int c_val;
-};
 typedef struct {
 	char *c_name;
 	int c_val;
 } CODE;
-#define prioritynames ((CODE *)(const struct __CODE []){ \
+#define prioritynames ((CODE *)(const CODE []){ \
 	{ "alert", LOG_ALERT }, { "crit", LOG_CRIT }, { "debug", LOG_DEBUG }, \
 	{ "emerg", LOG_EMERG }, { "err", LOG_ERR }, { "error", LOG_ERR }, \
 	{ "info", LOG_INFO }, { "none", INTERNAL_NOPRI }, \
 	{ "notice", LOG_NOTICE }, { "panic", LOG_EMERG }, \
 	{ "warn", LOG_WARNING }, { "warning", LOG_WARNING }, { 0, -1 } })
-#define facilitynames ((CODE *)(const struct __CODE []){ \
+#define facilitynames ((CODE *)(const CODE []){ \
 	{ "auth", LOG_AUTH }, { "authpriv", LOG_AUTHPRIV }, \
 	{ "cron", LOG_CRON }, { "daemon", LOG_DAEMON }, { "ftp", LOG_FTP }, \
 	{ "kern", LOG_KERN }, { "lpr", LOG_LPR }, { "mail", LOG_MAIL }, \