Optimize code size of `OatWriter::InitBssAndRelRoData()`.

The new code is functionally equivalent but much smaller as
we avoid duplicated inlined code from container functions.

clang++ optimizes the code similar to Optimizing compiler's
`SimplifyIfs()`, so we do not expect performance regressions
from additional conditional branches.

arm64 `OatWriter::InitBssAndRelRoData()` goes from 7325B
down to 4592B, a reduction of 2764B.

Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Bug: 181943478
Flag: EXEMPT refactor
Change-Id: I3b7bc01c63f3507af90cc208796f432ced3a4085
1 file changed