phpmyadmin: fix CVE-2015-7873

The redirection feature in url.php in phpMyAdmin 4.4.x before 4.4.15.1
and 4.5.x before 4.5.1 allows remote attackers to spoof content via the
url parameter.

Backport upstream commit to fix it:
https://github.com/phpmyadmin/phpmyadmin/commit/cd097656758f981f80fb9029c7d6b4294582b706



Signed-off-by: Wenzong Fan <wenzong.fan@windriver.com>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>