Since this is on by default now, we don't need a separate test
that has it enabled. Thus we can now remove one of the encoder
tests.
By not overriding the deblocking setting at all, the hash
changes for the other tests that use SEncParamExt.
Previously the default value of iMultipleThreadIdc was 0,
which made sure threads were used for the test with multiple
slices (if run on a multicore machine). Now the default is 1,
so multiple threads has to be requested.
Explicitly request 2 threads, to make sure the threading code is
tested, even on machines with only one core.