Fix tests after rebase of 36b6002396d onto 8504495ada4

Fix tests after rebase of 36b6002396d onto 8504495ada4

When we started to account for function stubs when determining our
PCC bounds and section bounds we stopped including padding to make PCC
bounds precise in the highest section that should be included in the PCC
range.  Instead we put such padding *after* that section.

Our patch handling IFUNC's was written in parallel, and its testcases
were using the previous setup (where PCC padding was included in the
last section).  Hence when calculating a fragment that we should see in
our testcase we took the highest address in the last RELRO section.

After the application of both patches that approach no longer works.
With the new mechanism for padding there is no longer in general a
guarantee that any value in the section table could correspond to the
PCC bounds (since the alignment of the first writeable section could be
high enough such that the PCC bounds are somewhere between the end of
the last RELRO section and the start of the first WRITE section).
However for all these testcases the start of the first WRITE section
seems good enough to not be flaky.