[Sanitizers] Move pvalloc overflow tests to common.

Summary:
Now all sanitizers with improved allocator error reporting are covered
by these common tests.

Also, add pvalloc-specific checks to LSan.

HWASan is not covered by sanitizer_common, hence its own pvalloc
and other allocator tests.

Reviewers: vitalybuka

Subscribers: srhines, kubamracek, delcypher, #sanitizers, llvm-commits

Differential Revision: https://reviews.llvm.org/D47970

llvm-svn: 334424