Skip two WatchpointAlgorithm tests for 32-bit lldb's

After iterating with the arm-ubuntu CI bot, I found the crash (a
std::bad_alloc exception being thrown) was caused by these two
entries when built on a 32-bit machine.  I probably have an assumption
about size_t being 64-bits in WatchpointAlgorithms and we have a
problem when it's actually 32-bits and we're dealing with a real
64-bit address.  All of the cases where the address can be represented
in the low 32-bits of the addr_t work correctly, so for now I'm
skipping these two unit tests when building lldb on a 32-bit host
until I can review that method and possibly switch to explicit
uin64_t's.
.