[package] Fix mysql dependencies

[package] Fix mysql dependencies

Trying to fix some issues with php5 I discoverd that php5's mysql extension doesn't load:

<snip>
root@OpenWrt:/tmp# php-cli -m
PHP Warning:  PHP Startup: Unable to load dynamic library '/usr/lib/php/mysql.so' - File not found in Unknown on line 0
[PHP Modules]
Core
ctype
curl
date
ereg
gettext
json
openssl
pcntl
pcre
posix
Reflection
session
sockets
SPL
sqlite3
standard
sysvmsg
sysvsem
sysvshm
zlib

[Zend Modules]
</snap>

After installing uclibcxx, the extension loads fine:

<snip>
root@OpenWrt:/tmp# opkg install uclibcxx
Installing uclibcxx (0.2.2-3) to root...
Downloading http://192.168.1.2:8081/brcm47xx/packages/uclibcxx_0.2.2-3_brcm47xx.ipk.
Configuring uclibcxx.
root@OpenWrt:/tmp# php-cli -m
[PHP Modules]
<...>
mysql
<...>

[Zend Modules]
</snap>

So the mysqlclient library needs uclibcxx, not only mysql-server. But since
mysql-server is depended of the mysqlclient library we can shorten its dependencies.

I also cross-checked that e.g. a mysql-enabled lighttpd shows the same behaviour
when uclibcxx is not installed.
<snip>
root@OpenWrt:/tmp/log/lighttpd# lighttpd -f /etc/lighttpd/lighttpd.conf
1970-01-01 05:07:30: (plugin.c.169) dlopen() failed for: /usr/lib/lighttpd/mod_mysql_vhost.so File not found
1970-01-01 05:07:30: (server.c.650) loading plugins finally failed
</snap>

Signed-off-by: Michael Heimpold <mhei@heimpold.de>
git-svn-id: svn://svn.openwrt.org/openwrt/packages@28083 3c298f89-4303-0410-b956-a3cf2f4a3e73