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

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

third_party/git/compat/hstrerror.c

@@ -0,0 +1,21 @@
+#include <string.h>
+#include <stdio.h>
+#include <netdb.h>
+
+const char *githstrerror(int err)
+{
+	static char buffer[48];
+	switch (err)
+	{
+	case HOST_NOT_FOUND:
+		return "Authoritative answer: host not found";
+	case NO_DATA:
+		return "Valid name, no data record of requested type";
+	case NO_RECOVERY:
+		return "Non recoverable errors, FORMERR, REFUSED, NOTIMP";
+	case TRY_AGAIN:
+		return "Non-authoritative \"host not found\", or SERVERFAIL";
+	}
+	snprintf(buffer, sizeof(buffer), "Name resolution error %d", err);
+	return buffer;
+}