Optimizing: Refactor call data in `LocationSummary`.

Reduce `LocationSummary` memory usage for instructions that
make no calls.

Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Bug: 181943478
Flag: EXEMPT refactor
Change-Id: Ie90d620fc50753431690a15a768e043b0f097beb