Sync mysqlnd version with PHP version

Since mysqlnd is solely developed in the php-src repository, it makes
not much sense to have its own version number, particularly since
nobody cares to update it.  Therefore we use PHP's version number, but
stick with the "mysqlnd" prefix which can be important to distinguish
the mysqli driver (libmysqlclient vs. mysqlnd).

Author: cmb69

.gitattributes

@@ -1,5 +1,4 @@
 # Replace $Id$ strings with 40-character hexadecimal blob object name.
-/ext/mysqlnd/mysqlnd.h          ident
 /ext/ext_skel.php               ident
 /ext/phar/phar/pharcommand.inc  ident
 /ext/dba/libinifile/inifile.c   ident

ext/mysqlnd/mysqlnd.h

@@ -21,8 +21,8 @@
 #ifndef MYSQLND_H
 #define MYSQLND_H
 
-#define PHP_MYSQLND_VERSION "mysqlnd 5.0.12-dev - 20150407 - $Id$"
-#define MYSQLND_VERSION_ID 50012
+#define PHP_MYSQLND_VERSION "mysqlnd " PHP_VERSION
+#define MYSQLND_VERSION_ID PHP_VERSION_ID
 
 #define MYSQLND_PLUGIN_API_VERSION 2