Drop XML_RPC of pear package

[Remi Collet]

Hi,

php-pear main package provides XML_RPC extension, but this in no more
used by PEAR since version 1.8.0.

I plan to drop this extension from php-pear

So, php-pear-XML-RPC review:
https://bugzilla.redhat.com/847690

Regards,
Remi.