QSV: re-use the encqsvInit MFX session when using the encode-only path.

This seems to work around a weird and obscure issue on some systems.



git-svn-id: svn://svn.handbrake.fr/HandBrake/trunk@5801 b64f7644-9d1e-0410-96f1-a4d463321fa5
QSV: MBBRC is actually Haswell-only.

This is confirmed by marketing material and testing with the 3257 driver on Ivy Bridge hardware.



git-svn-id: svn://svn.handbrake.fr/HandBrake/trunk@5802 b64f7644-9d1e-0410-96f1-a4d463321fa5