Disable -ftrivial-auto-var-init= for hot code

This helps to improve some benchmarks by 10%, e.g. decode_time
PCFullStackTest.VP9SVC_3SL_Low

Bug: 1020220, 977230
Change-Id: Ic992f1eec369f46a08e19eb33bc3a7c15c1e7c87
2 files changed