Small update to emacs example configuration

Since both tarballs and git now result in a "postgresql" directory
rather than a "pgsql" directory, adjust the example configuration to
look for the former.

src/tools/editors/emacs.samples

@@ -67,7 +67,7 @@
 (add-hook 'c-mode-hook
 	  (function
 	   (lambda nil
-	     (if (string-match "pgsql" buffer-file-name)
+	     (if (string-match "postgresql" buffer-file-name)
 		 (progn
 		   (c-set-style "bsd")
 		   (setq c-basic-offset 4)