Don't add spurious preceding newline if caption is not above a longtable

* lisp/org-latex.el (org-export-latex-tables): Don't add spurious
  preceding newline if caption is not above a longtable.

lisp/org-latex.el

@@ -1988,7 +1988,8 @@ The conversion is made depending of STRING-BEFORE and STRING-AFTER."
                              (if shortn (concat "[" shortn "]") "")
                              (or caption "")
 			     (if label (format "\\label{%s}" label) "")))
-			(if (and longtblp caption) "\\\\\n" "\n")
+			(if (and longtblp caption org-export-latex-table-caption-above)
+			    "\\\\\n" "\n")
                         (if (and org-export-latex-tables-centered (not longtblp))
                             "\\begin{center}\n")
                         (if (not longtblp)