Hi @suman_kumar_dey,
You seem to have multiple unofficial repos enabled on your ENV and clearly, there are conflicts.
The official CentOS 6 repos include PHP 5.3.3 only.
If you wish to install a higher version of PHP on a CentOS 6 machine, I recommend you use the Remi repos.
See: https://github.com/kaltura/platform-install-packages/issues/586
Make sure to only use the official CentOS repos and the Remi ones [again, only if a higher version of PHP is needed] and disable all the other unofficial ones. The Remi repo uses the same package names for PHP as the official PHP package names in the official CentOS/RHEL repo and also correctly declares the Provides and Obsoletes package metadata, thus enabling a smooth upgrade process.