Don't show the the branch selector button if javascript is enabled

Suggested-by: Olivier Ramonat <olivier@ramonat.fr>
Signed-off-by: Lars Hjemli <hjemli@gmail.com>

ui-shared.c

@@ -492,7 +492,7 @@ void cgit_print_pageheader(char *title, int show_search)
 		for_each_branch_ref(print_branch_option, cgit_query_head);
 		html("</select>\n");
 		html("</td><td>");
-		html("<input type='submit' id='switch-btn' value='..'>\n");
+		html("<noscript><input type='submit' id='switch-btn' value='..'></noscript>\n");
 		html("</td></tr></table>");
 		html("</form>\n");