030-iob18 uses a hack to work around the fuzzer not discovering RIOB18.IOB_Y0.SSTL*.IN

[hansfbaier]

For some reason the mentioned feature is only discovered for IOB_Y1, but not for IOB_Y0.
What seems to cause this is that the bit 39_127 from the manually identified feature
RIOB18.IOB_Y0.SSTL12_SSTL135_SSTL15.IN !38_126 39_127
disappears, when we have a differential input on IOB_Y0 (but not on IOB_Y1).
This creates a contradiction which makes segmatch report 0 candidates.

The python script to examine this and its output are attached here:
findsegbug.py.gz
result.txt

So, unfortunately currently we are inserting the mentioned feature manually in the Makefile,
which is a hack. It would be better to find out, how we could modify the fuzzer to find
the mentioned feature.