Update hwasan test to fix failure on older Android API versions.

In Android API < 30 there is no HWAsan instrumentation support for globals
so the test fails if API < 30 or if the target triple does not specify the API version.

Add -triple=aarch64-linux-android31 to enable global instrumentation. This is the
same triple as is used in the RUN line for -fsanitize=memtag-globals.

Differential Revision: https://reviews.llvm.org/D131806

Change-Id: I300703bd126b10e3c52505e23c78c5a48acb0309