Both 'platform_session/capability.h' and 'platform_session/connection.h'
do not contain platform-specific information. By moving them from
'include/platform/imx53/platform_session/' to 'include/platform_session/',
this patch enables other platforms to reuse them.
* Simplify IPU register definitions using templates
* Distinguish between i.MX53 QSB and SMD board in driver
* Support IPU specific overlay mechanism by framebuffer session extension