merge(third_party/git): Merge squashed git subtree at v2.23.0

Merge commit '1b593e1ea4' as 'third_party/git'

third_party/git/compat/win32/syslog.h

@@ -0,0 +1,20 @@
+#ifndef SYSLOG_H
+#define SYSLOG_H
+
+#define LOG_PID     0x01
+
+#define LOG_EMERG   0
+#define LOG_ALERT   1
+#define LOG_CRIT    2
+#define LOG_ERR     3
+#define LOG_WARNING 4
+#define LOG_NOTICE  5
+#define LOG_INFO    6
+#define LOG_DEBUG   7
+
+#define LOG_DAEMON  (3<<3)
+
+void openlog(const char *ident, int logopt, int facility);
+void syslog(int priority, const char *fmt, ...);
+
+#endif /* SYSLOG_H */