org-latex: Fix export of table.el tables with captions

* lisp/org-latex.el (org-export-latex-convert-table.el-table): Fix
format-string for insertion of captions.

This fixes a bug introduced in caa5da1 since when the caption itself
is not placed inside the caption command.

lisp/org-latex.el

@@ -1990,7 +1990,7 @@ The conversion is made depending of STRING-BEFORE and STRING-AFTER."
       (setq tbl (concat "\\begin{center}\n" tbl "\\end{center}")))
     (when floatp
       (setq tbl (concat "\\begin{table}\n"
-			(format "\\caption%s{%s}%s\n"
+			(format "\\caption%s{%s%s}\n"
 				(if shortn (format "[%s]" shortn) "")
 				(if label (format "\\label{%s}" label) "")
 				(or caption ""))