Don't set invalid iLoopFilterDisableIdc in RandomParamExtCombination
Log what uiDisableDeblockingFilterIdc was set to when printing an error message
Validate that iLoopFilterDisableIdc is set to a sensible value in ParamValidationExt

In WelsEncoderParamAdjust it is already clipped in the
same way, but here we should probably rather error out
than to silently clip it to the right range.
Merge pull request #1572 from mstorsjo/loopfilter-opts

Fixes relating to the loopfilter parameter