remove useless comments

The comments considering checking share/ directory was there for
almost 13 years, yet nobody ever trying to add the checking, and
there seems never any trouble for not checking it, then I think
we should remove those comments.

diff --git a/src/backend/postmaster/postmaster.c
b/src/backend/postmaster/postmaster.c
index 81cb585891..ecdc59ce5e 100644
--- a/src/backend/postmaster/postmaster.c
+++ b/src/backend/postmaster/postmaster.c
@@ -1581,11 +1581,6 @@ getInstallationPaths(const char *argv0)
                                 errhint("This may indicate an
incomplete PostgreSQL installation, or that the file \"%s\" has been
moved away from its proper location.",
                                                 my_exec_path)));
        FreeDir(pdir);
-
-       /*
-        * XXX is it worth similarly checking the share/ directory?  If the lib/
-        * directory is there, then share/ probably is too.
-        */
 }

-- 
Regards
Junwang Zhao