[sanitizer] Reduce stack depot size on Android.

Summary:
The default setting kTabSizeLog=20 results in an 8Mb global hash table,
almost all of it in private pages. That is not a sane setting in a
mobile, system-wide use case: with ~150 concurrent processes stack
depot will account for more than 1Gb of RAM.

Reviewers: kcc, pcc

Subscribers: srhines, kubamracek, llvm-commits

Differential Revision: https://reviews.llvm.org/D56333

Change-Id: Ib94e734640a1c1807741445d0ec385969e7f4c50
git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@350443 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed