Calculate a minimum intra value to be used in determining the
IIratio scores used in two pass, second pass.

This is to make sure sections that are low complexity" in the
intra domain are still boosted appropriately for KF/GF/ARF.

For now I have commented out the Q based adjustment of
KF boost.

Change-Id: I15deb09c5bd9b53180a2ddd3e5f575b2aba244b3