Without this patch, the --with-sanitizers config flag has no effect on
the copy of libsimplicity in Elements Core. This means that we aren't
running asan or tsan when we intend to, and also means that when fuzzing
we aren't instrumenting the Simplicity binary.
The result is extremely bad fuzz coverage and missed bugs.
ubsan suppression for simplicity sha256.c
ubsan detects when a left shift would overflow an integer type. This is
not UB (it would be if you tried to shift more than the type's width in
one shot) but "may be unintentional" and is therefore detected.
Add a whitelist to the giant list of whitelists.
