ui-shared: remove toggle_ssdiff arg to cgit_diff_link()

This argument is never used with a value other than zero, so remove it
and simplify the code.

Signed-off-by: John Keeping <john@keeping.me.uk>

ui-diff.c

@@ -97,7 +97,7 @@ static void print_fileinfo(struct fileinfo *info)
 	}
 	htmlf("</td><td class='%s'>", class);
 	cgit_diff_link(info->new_path, NULL, NULL, ctx.qry.head, ctx.qry.sha1,
-		       ctx.qry.sha2, info->new_path, 0);
+		       ctx.qry.sha2, info->new_path);
 	if (info->status == DIFF_STATUS_COPIED || info->status == DIFF_STATUS_RENAMED) {
 		htmlf(" (%s from ",
 		      info->status == DIFF_STATUS_COPIED ? "copied" : "renamed");
@@ -175,7 +175,7 @@ static void cgit_print_diffstat(const unsigned char *old_sha1,
 
 	html("<div class='diffstat-header'>");
 	cgit_diff_link("Diffstat", NULL, NULL, ctx.qry.head, ctx.qry.sha1,
-		       ctx.qry.sha2, NULL, 0);
+		       ctx.qry.sha2, NULL);
 	if (prefix) {
 		html(" (limited to '");
 		html_txt(prefix);