real_path: have callers use real_pathdup and strbuf_realpath

diff --git a/RelNotes b/RelNotes
index e29d6504d9e8fe45d3f7ff7f82f1e8f1f57b9f6f..d09c3d51093ac9e4da65e8a127b17ac9023520b5 120000 (symlink)
--- a/RelNotes
+++ b/RelNotes
@@ -1 +1 @@
-Documentation/RelNotes-1.5.6.txt
\ No newline at end of file
+Documentation/RelNotes/2.12.0.txt
\ No newline at end of file