This replaces the sanitizer tool list (used for generating
sanitizer_common configurations) with a tool list derived from
existing build system information.
Previously sanitizer_common had its own list of supported sanitizer
tools. This was bad because it was out of sync with the rest of the
build system. Notably it meant that the sanitizer_common runtime was
only being tested on Darwin the ASan dylib and not the other sanitizer
dylibs that are built for Darwin (LSan, TSan, and UBSan).
Unfortunately enabling the tests against other sanitizer dylibs has lead
to some test failures on Darwin. For now they've been marked as
unsupported until the failures can investigated properly.